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1
Paillé, Gilbert G. « The importance of forestry and forest engineering : Past present future ». Forestry Chronicle 79, no 5 (1 octobre 2003) : 876–81. http://dx.doi.org/10.5558/tfc79876-5.
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Until 1900, Canada had no foresters involved in logging, practising forestry or doing research. Forest engineering as a discipline held no importance whatsoever. The forest was simply exploited for its timbers and most of the forest products were sold abroad. During the next 50 years, four Canadian universities opened forestry schools, some research activities were organized by the federal government, provincial governments, and industry. However, the importance of forest engineering did not grow much. Since 1950, however, the situation was turned around completely, as was the industry. While forest operations were completely mechanised everywhere in Canada with machines or concepts often developed in the USA or in Scandinavia, more forestry schools were opened, the federal government opened forest research laboratories, provincial governments acquired more expertise in this field, and forestry equipment manufacturers did considerable development work. A national forest engineering research institute was even created. In the future, the forest community will have to team up to raise the profile of forest engineering. Key words: co-operation, forest engineering, forestry, forestry education, forestry research, sustainable management
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Goldenberg, A. A., J. Wiercienski, P. Kuzan, C. Szymczyk, R. G. Fenton et B. Shaver. « A remote manipulator for forestry operation ». IEEE Transactions on Robotics and Automation 11, no 2 (avril 1995) : 185–97. http://dx.doi.org/10.1109/70.370501.
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Sukhih, A., et O. Danilenko. « Actual aspects of forestry equipment operation ». Systems. Methods. Technologies, no 3(39) (2018) : 84–87. http://dx.doi.org/10.18324/2077-5415-2018-3-84-87.
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Kromhout, C. P. « 3. Co-operation in Forestry and Forestry Research in South Africa ». South African Forestry Journal 141, no 1 (juin 1987) : 3. http://dx.doi.org/10.1080/00382167.1987.9630251.
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Salmivaara, Aura, Samuli Launiainen, Jari Perttunen, Paavo Nevalainen, Jonne Pohjankukka, Jari Ala-Ilomäki, Matti Sirén et al. « Towards dynamic forest trafficability prediction using open spatial data, hydrological modelling and sensor technology ». Forestry : An International Journal of Forest Research 93, no 5 (21 mai 2020) : 662–74. http://dx.doi.org/10.1093/forestry/cpaa010.
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Abstract Forest harvesting operations with heavy machinery can lead to significant soil rutting. Risks of rutting depend on the soil bearing capacity which has considerable spatial and temporal variability. Trafficability prediction is required in the selection of suitable operation sites for a given time window and conditions, and for on-site route optimization during the operation. Integrative tools are necessary to plan and carry out forest operations with minimal negative ecological and economic impacts. This study demonstrates a trafficability prediction framework that utilizes a spatial hydrological model and a wide range of spatial data. Trafficability was approached by producing a rut depth prediction map at a 16 × 16 m grid resolution, based on the outputs of a general linear mixed model developed using field data from Southern Finland, modelled daily soil moisture, spatial forest inventory and topography data, along with field measured rolling resistance and information on the mass transported through the grid cells. Dynamic rut depth prediction maps were produced by accounting for changing weather conditions through hydrological modelling. We also demonstrated a generalization of the rolling resistance coefficient, measured with harvester CAN-bus channel data. Future steps towards a nationwide prediction framework based on continuous data flow, process-based modelling and machine learning are discussed.
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Kizha, Anil Raj, Han-Sup Han, Nathaniel Anderson, Anil Koirala et Libin T. Louis. « Comparing Hot and Cold Loading in an Integrated Biomass Recovery Operation ». Forests 11, no 4 (28 mars 2020) : 385. http://dx.doi.org/10.3390/f11040385.
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The balance of production activities at the landing is pivotal to the success of any forest harvesting operation and has a direct impact on the cost and efficiency of the enterprise. The primary objective of this study was to understand the operational characteristics of the loader in a hot operation (handling both sawlog and biomass components concurrently) and cold operation (handling biomass and sawlogs separately) for harvesting sawlogs and biomass. Systematic work sampling techniques were employed to obtain “snapshots” of the loader activities for a cable logging operation, including the interaction of the loader with other operational phases and delay time for both hot and cold configurations. The results show that for hot loading at the landing, the yarder was the most utilized machine (85%), and was the bottleneck of the operation, followed by the loader (70%). In the hot loading configuration, 39% of operational delay during truck loading was caused by the loader and was predominantly due to movement of the loader within or between the landings. This was followed by the yarder (19%, due to rigging activities) and the chaser (15%, to maintain the crews’ safety). In the cold loading configuration, delays due to the unavailability of roll-off bins constituted up to 77% of the operational delay. This suggests that the number of bins and trucks hauling biomass has a crucial role in the overall efficiency of the biomass harvesting system, and should be well balanced with loading capacity. Additionally, the choice of hot or cold biomass loading operations is highly dependent on the site and operating conditions.
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Cristan, Richard, W. Michael Aust, M. Chad Bolding et Scott M. Barrett. « Estimated Sediment Protection Efficiences for Increasing Levels of Best Management Practices on Forest Harvests in the Piedmont, USA ». Forests 10, no 11 (7 novembre 2019) : 997. http://dx.doi.org/10.3390/f10110997.
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In-stream watershed level evaluations confirm that application of recommended forestry best management practices (BMPs) can minimize sedimentation following management, while on-site erosion research shows that BMPs reduce erosion from individual forest operations, thus implying watershed-level sediment reductions. Assessments of forest operations and sediment have developed very few sediment delivery ratios (SDR). Linking BMP levels (low, standard recommendation, high) within specific forest operations to sedimentation could enable managers to evaluate BMP effects. Reported data regarding forest operations, erosion rates and SDR by forest operation, and BMP implementation levels were sufficient within the Piedmont region to allow approximations of sediment delivery and BMP efficiency. Existing United States Department of Agriculture (USDA) Forest Service reports and published erosion and sediment research were used to comprise the following method. For regional annual harvests, estimated sediment deliveries (Mg year−1) = annual harvest area (ha year−1) × weighted average erosion rate from all forest operations (Mg ha−1 year−1) × SDR (unitless ratio). Weighted average erosion rates for all forest operations were determined by applying areas in each operational activity (%) × estimated erosion per operation (Mg ha−1 year−1). In comparing published data, standard BMPs reduced estimated sedimentation by 75% compared to low BMP implementation levels. This supports forestry BMP efficiency findings reported for sediment removals in watershed studies. Higher levels of BMP implementation were estimated to potentially remove nearly all forest operation-produced sediment. Values of this pilot study should be viewed cautiously, as estimates were based on limited data, estimated operations, and limited SDRs; are based on BMP categories that vary between states; and address only one year following harvests. However, the approach provided approximations that facilitate BMP evaluations and can be improved with additional data. This methodology highlights the importance of accurate estimates of erosion rates, SDRs, sediment masses, and area for operations. This supports the importance of state programs, which have increased BMP implementation rates and compliance options with BMP program maturation.
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Warguła, Łukasz, Mateusz Kukla, Piotr Krawiec et Bartosz Wieczorek. « Impact of Number of Operators and Distance to Branch Piles on Woodchipper Operation ». Forests 11, no 5 (25 mai 2020) : 598. http://dx.doi.org/10.3390/f11050598.
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Branch chipping machines with low-power engines are distinguished with an intermittent operation due to a periodical supply of branches. A conventional drive speed control of these machines is not adapted to adjust the operating mode depending on frequency of material supply for shredding. This article discusses the issues related to the assessment of the application of adaptive systems similar in design to start–stop systems used in vehicles, as necessary in the driving of this type machine. During testing, an impact of a distance between a branch pile from the woodchipper, a number of operators on frequency of drive unit operating condition changes, and the mass and volume output (productivity) were considered. A percentage ratio of the active and passive (idle) operation in selected conditions of use was also determined. A low-power 9.5 kW engine-powered cylindrical-type woodchipper was used for testing. Material chopped in the chipper was freshly cut branches of oaks (Quercus L. Sp. Pl. 994. 1753) with a diameter in the largest cross-section ca. 80 mm and moisture content ca. 25%. Piles of branches were located at three different distances from the chipper, i.e., 3 m, 9 m and 15 m. Branches to the chipper were fed by one or two operators. It was demonstrated that the idle run time in tested conditions with one operator could be from 43% to 71% of the entire operating time. Frequency of operating condition changes when only one operator worked and fluctuated from ca. 6 to 2 times per minute. Increasing the number of operators from one to two had a slight impact on the frequency of operating condition changes (by ca. 7%) at the shortest distance from the chipper (3 m). However, at larger distances, the additional operator may increase the frequency of operating condition changes of the chipper by 77% for 9 m distance and 85% for 15 m distance. The mass and volumetric output of the cylindrical chipper in the most advantageous case is equal to 0.66 t/h and 3.5 m3/h, respectively. The increase of the branch pile distance from the chipper causes a drop in mass output by 32%, and volumetric output by 33.5%. The results of the tests confirmed the necessity for the development of low-power chipping machines designed for clearing operations rather than industrial production of biomass. A direction for development could be systems that adapt driving units to operating conditions, depending on a demand for the chipping process.
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Nový, Vladislav. « Optimisation of timber harvesting work of Logset 5H medium power harvester ». Forestry Journal 61, no 4 (1 décembre 2015) : 246–51. http://dx.doi.org/10.1515/forj-2015-0033.
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Abstract This article analyses field measurements of harvestor operation activities with the aim to search for optimum production conditions of the machine from the point of fuel consumption and operation efficiency. All applied measurement and calculation approaches are based on the methodology for the evaluation of the natural principle of minimax. This principle is one of the most complex decision-making principles in deploying technologies in these activities with minimum energy costs for machine operation, and with regard to the economy of operating these techniques. The measured and calculated values revealed that considering the stated criteria the optimum conditions of the tested machine occurred when a harvested stem had a volume between 0.2 and 0.4 m3.
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Berg, Simon, Mika Yoshida, Rin Sakurai et Hideo Sakai. « Productivity of loaders and forwarders in Japanese forestry operation conditions ». Journal of Forest Research 23, no 3 (3 mai 2018) : 149–55. http://dx.doi.org/10.1080/13416979.2018.1469208.
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Brown, Mark W. « Evaluation of the Impact of Timber Truck Configuration and Tare Weight on Payload Efficiency : An Australian Case Study ». Forests 12, no 7 (28 juin 2021) : 855. http://dx.doi.org/10.3390/f12070855.
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The forest industry tends to plan, and model transportation costs based on the potential payload benefits of increased legal gross vehicle weight (GVW) by deploying different configurations, while payload benefits of a configuration can be significantly influenced by the vehicle design tare weight. Through this research the relative benefit of increased legal GVW of different configurations is compared across Australia over a 13-year period from 2006 to 2019, by examining data collected post operation across multiple operations. This approach is intended to offer realistic insight to real operations not influenced by observation and thus reflect long-term operating behaviour. The inclusion of the three most common configuration classes in Australian forestry over a 13-year period has also allowed the exploration of load management between configurations and potential trends over time. When considering the legal GVW and the tare weight impacts across the fleets, the semi-trailer has an 8 t payload disadvantage compared to B-Doubles and 19.6 t disadvantage compared to road trains.
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Zolotnytska, Y. « Forestry branch of Zhytomyr region : problems and efficiency of operation ». Scientific Horizons 72, no 11 (2018) : 82–86. http://dx.doi.org/10.33249/2663-2144-2018-72-11-82-86.
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Siebert, Stephen F., James P. Lassoie et Mark B. Lapping. « Fuelwood Cooperatives : Their Role and Development in the Northeastern United States ». Northern Journal of Applied Forestry 3, no 4 (1 décembre 1986) : 137–39. http://dx.doi.org/10.1093/njaf/3.4.137.
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Abstract Characteristics of and requirements for successful establishment and operation of fuelwood cooperatives were assessed by evaluating nine currently or recently operating New England fuelwood cooperatives. Three types of cooperatives were identified—consumer, processing, and producer. The importance of maximizing local member-patron participation in all facets of cooperative action and of restricting government and professional forestry involvement to educational and forestry assistance are illustrated. Churches are identified as a potential source of assistance in attempts to establish and operate fuelwood cooperatives. North. J. Appl. For. 3:137-139, Dec. 1986.
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Lee, Eun-Jai, Yun-Sung Choi, Min-Jae Cho, Koo-Hyun Cho, Jae-Heun Oh, Sang-Kyun Han et Sang-Jun Im. « A Literature Review on Cable Extraction Practices of South Korea : 1990–2020 ». Forests 12, no 7 (12 juillet 2021) : 908. http://dx.doi.org/10.3390/f12070908.
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Cable yarding technology remains the most effective operation in steep terrain harvesting systems; however, it has limitations and challenges. Using cable yarders (tractor-, truck-, and excavator-based) to extract tree lengths and whole trees has been common since the late 20th century in South Korea, and cable yarding operations were developed in the late 1800s in the United States and Europe. Machine potential and limitations must be understood to ensure the widespread use of technology, strong cooperation, and optimal selection of machinery size. We reviewed the literature on tower yarder performances from 1990–2021 to determine the alteration of yarders and its productivity pattern and obtained 23 papers; <2 publications per year discussed the determination of cable yarding productivity. We selected independent variables (e.g., silvicultural treatment, harvesting method, and cycle log volume) for cable yarding that would likely affect productivity. Data were analyzed to compare productivities under silvicultural treatment, the harvesting method, and yarding direction and identify the interaction mechanical power (i.e., lifting capacity and machine power), yarding distance, and slope. Cable yarder productivity rates generally depended on the silvicultural treatment, harvesting method, and yarding direction, particularly in clear-cut, tree-length, and uphill yarding operation activities. The lifting capacity, machine power, and slope had no significant correlation with yarders’ productivity, particularly in thinning operations, whereas, in clear-cut productivity, it was influenced by these variables. The results contribute to improving operation activities for cable yarding systems and towards future research directions.
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Boston, Kevin, et Glen Murphy. « Value Recovery from Two Mechanized Bucking Operations in the Southeastern United States ». Southern Journal of Applied Forestry 27, no 4 (1 novembre 2003) : 259–63. http://dx.doi.org/10.1093/sjaf/27.4.259.
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Abstract The value recovered from two mechanized bucking operations in the southeastern United States was compared with the optimal value computed using an individual-stem log optimization program, AVIS. The first operation recovered 94% of the optimal value. The main cause for the value loss was a failure to capture potential sawlog volume; logs were bucked to a larger average small end diameter than necessary. The result was that a portion of the stem with potential sawlog volume was being converted into lower value pulpwood. Although the value loss was relatively small, the length measurements were outside of the acceptable range and the machine needed to be recalibrated. The second operation recovered only 58% of the optimal value. The main cause of loss was poor length measurement, producing a number of short logs that would have been rejected as chip-and-saw logs. Statistical quality control charts from both operations show that logs were being cut too long for the first operation studied and too short for the second operation. These low cost control methods should be required for monitoring mechanized bucking operations. We believe they will help to reduce the value lost from inconsistent measurements. South. J. Appl. For. 27(4):259–263.
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Cromwell, Connor, Jesse Giampaolo, Joseph Hupy, Zachary Miller et Aishwarya Chandrasekaran. « A Systematic Review of Best Practices for UAS Data Collection in Forestry-Related Applications ». Forests 12, no 7 (20 juillet 2021) : 957. http://dx.doi.org/10.3390/f12070957.
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Recent advancements in unmanned aerial systems and GPS technology, allowing for centimeter precision without ground-based surveys, have been groundbreaking for applications in the field of forestry. As this technology becomes integrated into forest management approaches, it is important to consider the implementation of proper safety and data collection strategies. The creation of such documentation is beneficial, because it allows for those aspiring to create a UAS program to learn from others’ experiences, without bearing the consequences of past blunders associated with the development of these practices. When establishing a UAS program, it is pertinent to deeply research the necessary equipment, create documentation that establishes operational norms, and develop standards for in-field operations. Regarding multispectral vs. RGB sensor payloads, the sensor selection should be based upon what type of information is desired from the imagery acquired. It is also important to consider the methods for obtaining the most precise geolocation linked to the aerial imagery collected by the sensor. While selecting the proper UAS platform and sensor are key to establishing a UAS operation, other logistical strategies, such as flight crew training and operational planning, are equally important. Following the acquisition of proper equipment, further preparations must be made in order to ensure safe and efficient operations. The creation of crew resource management and safety management system documentation is an integral part of any successful UAS program. Standard operating procedure documents for individual tasks and undertakings are also a necessity. Standardized practices for the scheduling, communication, and management of the UAS fleet must also be formulated. Once field operations are set in motion, the continuous improvement of the documentation and best practices is paramount.
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Phelps, Keith, Patrick Hiesl, Donald Hagan et Althea Hotaling Hagan. « The Harvest Operability Index (HOI) : A Decision Support Tool for Mechanized Timber Harvesting in Mountainous Terrain ». Forests 12, no 10 (25 septembre 2021) : 1307. http://dx.doi.org/10.3390/f12101307.
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Forest operations have become increasingly reliant on mechanized harvesting equipment due to their increased production capacities in competitive markets. However, operating heavy machinery in mountainous terrain poses numerous operational and accessibility challenges from steep slopes, erosion risk, and poor road access. Geographic Information Systems (GIS) have effectively been used in various studies to identify areas in mountainous landscapes that pose no or reduced constraints for harvesting equipment operation. This study introduces the Harvest Operability Index (HOI), which rates a landscape for wheel-based equipment suitability (i.e., operability) and assesses its application in 13,118 ha of the Jocassee Gorges Natural Resource Area, situated on the Southern Blue Ridge Escarpment in Northwestern South Carolina, USA. The HOI incorporated slope, distance from roads, cost distance from major highways, primary Streamside Management Zones (SMZ), stand age, and soil suitability ratings for harvesting equipment operation. Upon reclassification to a 5-tier suitability scale, the HOI revealed 60% (7824 ha) of the case study area was in a Slope Exclusion Zone, or land area inoperable for wheel-based equipment due to steep slopes. Values of Very Poor and Poor Operability occupied less than 1% (213 ha) of land area whereas Moderate Operability values were 9% of the land area (1257 ha). Values of Good Operability occupied 18% (2442 ha) of the study area and values of Very Good Operability occupied 10% (1381 ha). These results reflected the challenges of mechanized harvesting in the study area due to a preponderance of steep slopes and poorly suited soil. Our model delineated areas of high equipment operability in two locations in the study area, despite a lack of recent logging activity around them. Results of the HOI analysis offer an accessible way for forest managers to better prioritize logging operations in areas that are highly operable and therefore more likely to possess lower overall harvesting costs, for wheel-based harvesting systems. The HOI can also be used as an asset for other forest management priorities, such as identifying highly operable areas that can use timber harvesting for fuel reduction and ecological restoration in fire-dependent forests. This model can be applied to various other regions where mountainous terrain poses a limitation to wheel-based harvesting equipment operation- and where wheel-based equipment is essential to advance the pace and scale of harvesting for ecological restoration.
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Kopseak, Hrvoje, Zdravko Pandur, Marin Bačić, Željko Zečić, Hrvoje Nevečerel, Kruno Lepoglavec et Marijan Šušnjar. « Exhaust Gases from Skidder ECOTRAC 140 V Diesel Engine ». Forests 13, no 2 (8 février 2022) : 272. http://dx.doi.org/10.3390/f13020272.
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During forest harvesting operations, exhaust emissions from forest vehicles are released at different levels depending on several variables. This pollution released into the atmosphere is considered one of the main anthropogenic factors that negatively affect forest ecosystems. In this study, we analyzed exhaust emissions from a skidder diesel engine during various engine loads. Measurements were done on an ECOTRAC 140 V skidder with the water-cooling diesel engine and a built-in catalyst with an SCR system. The composition and amount of exhaust gases (CO, CO2, O2, NOx,) at different loads of the diesel engine of the skidder and engine temperature were measured using a MAHA MET 6.3 measuring device. The amount of exhaust gases was analyzed in relation to the engine speeds, engine temperatures, and the European emission standards for engines used in nonroad mobile machinery (NRMM). Influences of catalyst systems and recommendations for more environmentally friendly forest harvesting practices are addressed. With the engine unloaded, the amount of CO2 increased when engine speed was increased, while other amounts of exhaust gas decreased. During the cold start, the concentrations of hydrocarbons and nitrogen compounds were high. The composition of the exhaust gas was affected by the exhaust reduction system installed in the tractor and the amount of the exhaust gas was dependent on the engine load. The skidder engine met the requirements of the exhaust gas standards EPA/COM IIIB Tier 4 (I) under which it is declared. With a load engine during winch operation (2300 rpm), NOx amounts mostly exceed the limit values of the standard. Exhaust emissions can be reduced at various operating levels by utilizing the most environmentally friendly technologies and following the correct procedures, such as warming the engine up to operating temperature prior to operation and operating in the most favorable mode with optimal speed. The regular reduction of exhaust limit values to newer stages of the standard therefore leads to the continuous development of engines and forest vehicles in general.
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Ezzati, Sättar, Farzam Tavankar, Mohammad Reza Ghaffariyan, Rachele Venanzi, Francesco Latterini et Rodolfo Picchio. « The Impact of Weather and Slope Conditions on the Productivity, Cost, and GHG Emissions of a Ground-Based Harvesting Operation in Mountain Hardwoods ». Forests 12, no 12 (23 novembre 2021) : 1612. http://dx.doi.org/10.3390/f12121612.
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Mountainous hardwood mixed stands offer challenges to timber harvesting operations in practice, including a harsh climate, variable topography, steep terrain, and large-sized timbers. This paper aims to develop productivity and cost models for a mountain-ground-based harvesting operation across the terrain (e.g., slope conditions), stand (e.g., tree volume) environmental (e.g., weather), and yard (e.g., winching distance) variables and to assess GHG emissions related to the equipment in use. This development was implemented in a timber harvesting practice under single-tree selection in mountainous forests of Iran where a motor-manual chainsaw is used for felling and a rubber-tired cable skidder is used for log extraction. The average delay-free productivity was 4.55 m3 for felling and 14.73 m3 h−1 for skidding. Lower production costs and higher productivity rates were observed over the gentle slopes and in sunny conditions. The average production costs ranged between USD 4.27 m−3 for felling and USD 5.35 m−3 for skidding. The average emissions ranged between 0.96 kg m−3 for felling and 7.06 kg m−3 for skidding in snowy conditions over steep slopes. The study’s results confirm avoiding harvesting operations on steep slopes (greater than 35%) and in extreme weather conditions to obtain higher work efficiency and to minimize adverse effects of machinery on forest ecosystems. The results should be of use to harvest managers and forest planners considering the application of ground-based harvesting operations using a semi-mechanized system on a range of operating conditions in mountain hardwood stands.
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Yao, Ruting, Yili Zheng, Fengjun Chen, Jian Wu et Hui Wang. « Research on Vision System Calibration Method of Forestry Mobile Robots ». International Journal of Circuits, Systems and Signal Processing 14 (12 janvier 2021) : 1107–14. http://dx.doi.org/10.46300/9106.2020.14.139.
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Forestry mobile robots can effectively solve the problems of low efficiency and poor safety in the forestry operation process. To realize the autonomous navigation of forestry mobile robots, a vision system consisting of a monocular camera and two-dimensional LiDAR and its calibration method are investigated. First, the adaptive algorithm is used to synchronize the data captured by the two in time. Second, a calibration board with a convex checkerboard is designed for the spatial calibration of the devices. The nonlinear least squares algorithm is employed to solve and optimize the external parameters. The experimental results show that the time synchronization precision of this calibration method is 0.0082s, the communication rate is 23Hz, and the gradient tolerance of spatial calibration is 8.55e−07. The calibration results satisfy the requirements of real-time operation and accuracy of the forestry mobile robot vision system. Furthermore, the engineering applications of the vision system are discussed herein. This study lays the foundation for further forestry mobile robots research, which is relevant to intelligent forest machines.
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Karlušić, Juraj, Mihael Cipek, Danijel Pavković, Juraj Benić, Željko Šitum, Zdravko Pandur et Marijan Šušnjar. « Simulation Models of Skidder Conventional and Hybrid Drive ». Forests 11, no 9 (23 août 2020) : 921. http://dx.doi.org/10.3390/f11090921.
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The paper presents a hypothetical conversion of a conventional cable skidder powertrain to its hybrid version. Simulations of skidder operation were made for two existing forest paths, based on the technical characteristics of the engine, transmission system and the characteristics of the winch. Fuel and time consumption were calculated per working cycle considering the operating conditions (slope, load mass). The model was then converted to a hybrid version by adding a battery energy storage system in parallel with the electrical power generator and by employing an energy management control strategy. The dimensions of the battery and the power generator were chosen based on the characteristics of the existing winch with the aim of completely taking over its operation. The management strategy was selected using the specific fuel consumption map. All simulations were repeated for the hybrid drive under the same operating conditions. The results show that fuel savings of around 13% can be achieved with the selected hybrid drive and steering strategy.
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Savinainen, M. S., Nyberg et Merivirta. « 31 Efficiency of occupational health co-operation in small forestry enterprises ». Occupational and Environmental Medicine 70, Suppl 1 (septembre 2013) : A11.1—A11. http://dx.doi.org/10.1136/oemed-2013-101717.31.
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Brantschen, Evelyn Coleman. « Wo entsteht Nachhaltigkeit ? Ein Blick in die internationale Forstpolitik der Schweiz | Where is Sustainability Developed ? Elements of Switzerland’s International Forest Policy ». Schweizerische Zeitschrift fur Forstwesen 151, no 12 (1 décembre 2000) : 515–18. http://dx.doi.org/10.3188/szf.2000.0515.
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Bilateral development co-operation projects in forestry have been continuously enlarging their field of action to encompass national policies for forestry and other relevant sectors, with the aim of taking better account of the situation in the country in question. At the same time, international (multilateral)political processes are attempting to create favourable conditions for countries to implement a sustainable forest management. In both cases, the national level is decisive, showing the potential of national forest programmes. By following the steps that led to development co-operation as it is today, the author derives elements of an international forest policy for Switzerland and views its actual engagement.
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DeLasaux, Mike J., Bruce R. Hartsough, Raffaele Spinelli et Natascia Magagnotti. « Small Parcel Fuel Reduction with a Low-Investment, High-Mobility Operation ». Western Journal of Applied Forestry 24, no 4 (1 octobre 2009) : 205–13. http://dx.doi.org/10.1093/wjaf/24.4.205.
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Abstract Fuel reduction treatments are especially urgent near homes, where a stand replacement fire would also endanger property and human lives. However, the forested properties associated with homes are often too small for cost-effective mechanized fuel treatment performed with traditional methods and equipment. This project tested a small rubber-tracked skid-steer specially modified for forestry operations that can provide all the functions of a complete harvesting system. The skid-steer can, alternately,carry a hot saw for tree felling, a processor to delimb and buck felled trees, a brush cutting head for mastication, and a log-grapple to transport logs and trees. All of the equipment can be transported on a trailer pulled by a heavy pickup truck, which makes for fast, economical movement between project sites. The study confirmed that this system is well suited to small-parcel conditions around home sites and performs best on even terrain, moderate slopes, and softwood trees with a dbh between 5 and 8 in. It took from 7 to 15 productive machine-hours ac−1 to perform all treatment phases (i.e., mastication, felling, processing, and skidding). The occurrence of delays significantly increased this figures, bringing the average 9.7 productive hours ac−1 to 13.5 worksite hours. Treatment cost was estimated at $480 ac−1 and $1,146 ac−1 for whole-tree and cut-to-length harvesting, respectively. In addition to offering a reasonable treatment cost, the system has the advantage of requiring a low investment, which allows small-scale enterprises to get into the business.
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Stuart, William B. « Checking Our Foundations : Matthews' Least Cost Models Revisited ». Southern Journal of Applied Forestry 27, no 1 (1 février 2003) : 30–35. http://dx.doi.org/10.1093/sjaf/27.1.30.
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Abstract Logging in the U.S. South at the beginning of the twentieth century was an operating unit of manufacturing and therefore treated as a cost center. Around the middle of the century, it shifted to a service provided by standalone firms operating as “for profit” businesses. The engineering economy approach of cost control from the earlier era of company logging operations continues to be used by professionals. Increasing production to distribute “fixed costs” is a key element of many cost control approaches. The most common of these, the model for identifying the point of operation where average total cost per unit is minimized, exemplified by Matthews' road spacing model, is revisited considering the complexities of the modern operating environment and the competing objectives of land management, wood supply, and for-profit contractors. South. J. Appl. For. 27(1):30–35.
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D'Eon, Robert G., Daryll Hebert et Stephen L. Viszlai. « An ecological rationale for sustainable forest management concepts at Riverside Forest Products, southcentral British Columbia ». Forestry Chronicle 80, no 3 (1 juin 2004) : 341–48. http://dx.doi.org/10.5558/tfc80341-3.
Texte intégralRésumé :
Riverside Forest Products (Kelowna, British Columbia) has embraced a sustainable forest management approach for the management of one its forest tenuresTree Farm License 49. This document discusses the rationale behind many of the concepts within this approach in the context of current ecological theory. We focus specifically on the following concepts: (1) forest retention, (2) ecosystem representation, (3) ecological contributions from unharvested forests, (4) zoning and the TRIAD approach, (5) stand-level habitat elements and landscape-level features, and (6) ecological indicators. This document provides an example of the application of current ecological theory within a commercial forestry operation in Canada and is thus broadly applicable to foresters, forest managers, and researchers in most jurisdictions. Key words: British Columbia, criteria and indicators, ecological representation, forest retention, sustainable forest management, Riverside Forest Products, TRIAD
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Melyakova, O. A., G. V. Kuchumova et O. V. Chursin. « Negative environmental factors at forestry facilities in the Ural Federal district ». IOP Conference Series : Earth and Environmental Science 937, no 3 (1 décembre 2021) : 032119. http://dx.doi.org/10.1088/1755-1315/937/3/032119.
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Abstract Information on the forestry facilities operation, number of employees, regulated activities, statistical data on natural fires are taken from public access sources and do not provide a comprehensive analysis in the Ural Federal District. The article makes an attempt to briefly study the activities of several forestry enterprises in the Tyumen and Sverdlovsk regions.
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Pranoto, Kris, Widia Rahmawati Pahilda, Muhammad Sonny Abfertiawan, Apridawati Elistyandari et Andi Sutikno. « Activated Sludge Technology to Treat Wastewater from Offices and Residential Areas PT Kaltim Prima Coal ». Indonesian Mining Professionals Journal 1, no 1 (17 décembre 2019) : 61–66. http://dx.doi.org/10.36986/impj.v1i1.14.
Texte intégralRésumé :
In Indonesia, coal mining operations generally involve a huge number of workers. This condition causes its own challenges in managing environmental impacts that potentially generated from human activities. One of them is domestic wastewater. Domestic waste water is waste water that comes from activities of daily living of humans related to water usage. In mining operations, domestic wastewater is generated from office and residential areas. Because of the potential impact on the environment, domestic wastewater must be treated before flowing to natural water bodies. Since the beginning of mining operations in 1990s, PT Kaltim Prima Coal has been building and operating Domestic Wastewater Treatment Plant (IPALD) to treat domestic wastewater resulting from offices and residential areas. There are 12 IPALDs with activated sludge technology operating in the PT KPC area. Active sludge is one of the domestic wastewater treatment technologies by utilizing the role of aerobic bacteria to degrade organic material contained in domestic wastewater. This paper is presented to describe the performance of activated sludge technology usedin the KPC’s IPALD and the challenges faced in its operation. One of the challenges faced is the fulfillment of water quality standards in Minister of Environment and Forestry Decree No. P. 68 of 2016 concerning Domestic Wastewater Quality Standards. The latest quality standards regulate the effluent concentration of IPALD more stringent than before and there are new parameters, including ammonia which requires attention in the operation of IPALD.
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Sjöström, Johan, Frida Vermina Plathner et Anders Granström. « Wildfire ignition from forestry machines in boreal Sweden ». International Journal of Wildland Fire 28, no 9 (2019) : 666. http://dx.doi.org/10.1071/wf18229.
Texte intégralRésumé :
Several large Swedish wildfires during recent decades were caused by forestry machinery in operation, fires for which there is still no characterisation. We combined 18 years of data on dispatches, weather and fire danger and interviewed forestry workers to understand the spatial, temporal and weather distributions of these fires, and their underlying mechanisms. We estimate the average annual number of ignitions from forestry machinery in Sweden at 330–480 (2.0±0.4 ignitions per 1000ha clear-felling) of which 34.5 led to firefighter dispatches, constituting 2.2% of all forest fire dispatches and 40% of area burnt. Soil scarification causes the most ignitions and the main mechanism is likely high-inertia contact between discs and large stones, causing sparks igniting dry humus or moss, countering reports suggesting that such metal fragments cannot fulfil ignition requirements. We found a spatial relationship between forestry machine ignitions and abundance of large stones, represented by a Boulder Index generated from a nationwide dataset. Further, 75% of the dispatches occurred on days with relative humidity <45%, Duff Moisture Code (Canadian system) >26 and Fire Weather Index >12. 75% of the area burned when Fire Weather Index was >20. Results suggest machine-caused forest fires can be largely avoided by cancelling operations in stony terrain during high-risk weather.
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Huang, Jia Rong, Dong Feng Yan, Fang Guo et Xiao Xu He. « Reforming Instruction of Forestry Specialty with Information Technology ». Advanced Materials Research 271-273 (juillet 2011) : 1463–67. http://dx.doi.org/10.4028/www.scientific.net/amr.271-273.1463.
Texte intégralRésumé :
Forestry informationization is an important part of Forestry ecological construction, which needs a large number of high-level mastery of information technology expertise of forestry specialty, so exploration of effective way to integrate instruction of forestry specialty and information technology is the important task of teaching reforms. This paper describes the basic objectives of forestry specialty training and the importance and necessity of the integration of information technology and forestry specialty, and detailed objectives and integration method. The integration methods are to establish the course systems of computer expertise and forestry specialty special knowledge, to improve the contents of information technology courses, to combine information technology courses with practical teaching considering all levels of forestry production, operation and management information needs. Meanwhile, The platform can be established for students to master the ability of information technology through graduation thesis, innovative project, teachers ' scientific research, other non-curricular teaching and laboratory opening session, and network platform, database technology, multimedia technology, and test database systems, teaching methods.
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Attebrant, M., J. Winkel, S. E. Mathiassen et A. Kjellberg. « Shoulder-arm muscle load and performance during control operation in forestry machines ». Applied Ergonomics 28, no 2 (avril 1997) : 85–97. http://dx.doi.org/10.1016/s0003-6870(96)00050-6.
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Zaikin, Anatoliy N., Vladimir V. Sivakov, Nikolay A. Bulkhov, Svetlana A. Konshakova et Sergey G. Kuznetsov. « The Use of Logging Machinery Sets in the Republic of Bashkortostan ». Lesnoy Zhurnal (Forestry Journal), no 3 (1 juin 2022) : 139–52. http://dx.doi.org/10.37482/0536-1036-2022-3-139-152.
Texte intégralRésumé :
The disintegration of the integrated logging enterprises, as well as of the forestry enterprises and the reduced attention of the authorities to the production of specialized machinery and equipment, the logging production process, have led to a decline in the equipment of the logging enterprises with specialized machinery and the effective organization of their operation. Small, privately owned, poorly equipped with machinery logging companies have emerged. Practically we reverted to the technology of the 1960s. Foreign chainsaws are used for felling, delimbing and crosscutting. The skidding operation practically uses general-purpose tractors of МТЗ-80(82) type with the simplest technological equipment – a set of chokers. Some of the larger companies use foreign harvesters and forwarders. According to our research, forestry farms of the Republic of Bashkortostan are in a similar position. In order to increase the level of equipment and improve the organization of its work at the enterprises of the Republic of Bashkortostan we have considered and proposed for use a number of machinery sets. However, practice shows that it is not enough to acquire and equip the production with modern machinery and equipment. A production process must be set up to ensure the effective operation of these machines. Logging as a complex, multi-operated, discrete process can be carried out using a variety of technologies. The most common technology nowadays is the logging and hauling of assortments, for which various harvesting machines and equipment can be used. For the effective operation, harvesting machines performing individual operations are combined into machinery sets. However, current practice shows that it is not possible to match machines and equipment with the same or slightly different capacities. Therefore, the output of such sets is usually equal to, or even lower than, the output of the operation with the lowest capacity. In order to increase the output of the machinery set to the output of the leading machine (the machine with the highest capacity), it is necessary to calculate the modes of operation of machines for specific operating conditions. There are five sets of logging machines offered. The costs that the use of each of them will require are calculated. On the basis of the obtained data it is concluded that in the conditions of the Republic of Bashkortostan it is most economically feasible to use the following set: chainsaw for felling, choker tractor for skidding, two chainsaws for delimbing and crosscutting, lumber carrier for hauling.
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le Mar, K., et C. McArthur. « Changes in marsupial herbivore densities in relation to a forestry 1080-poisoning operation ». Australian Forestry 64, no 3 (janvier 2001) : 175–80. http://dx.doi.org/10.1080/00049158.2001.10676183.
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Qinglin, Li, Zhang Haitang et Yang Jinshan. « The effect of cutting operation on higher plants diversity ». Journal of Northeast Forestry University 6, no 3 (septembre 1995) : 34–37. http://dx.doi.org/10.1007/bf02880630.
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Iwaoka, Masahiro, Kazuhiro Aruga, Rin Sakurai, Koo Hyun Cho, Hideo Sakai et Hiroshi Kobayashi. « Performance of Small Harvester Head in a Thinning Operation ». Journal of Forest Research 4, no 3 (novembre 1999) : 195–200. http://dx.doi.org/10.1007/bf02762248.
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Schweier, Janine, et Christian Ludowicy. « Comparison of A Cable-Based and a Ground-Based System in Flat and Soil-Sensitive Area : A Case Study from Southern Baden in Germany ». Forests 11, no 6 (29 mai 2020) : 611. http://dx.doi.org/10.3390/f11060611.
Texte intégralRésumé :
The results of this study showed that the application of cable-based systems in flat terrain must not necessarily be more cost intensive than its application in other terrains. In recent years, criteria other than purely economic ones have been taken into account in forest management decisions, with the aim of avoiding ecosystem damage and promoting better ecosystem services. Since precipitation in winter is becoming more intensive and weeks with frozen soils are becoming rare, one option might be the use of cable-based instead of ground-based extraction systems. Both vary in terms of economy and flexibility. Thus, it is important to make reliable estimates of potential costs and benefits before an operation is conducted. The aim of this study was to analyze a cable-based and a ground-based extraction system that could be applied to a forest stand in a flat and soil-sensitive area. The study, based on a cable-based operation, was conducted in a mixed forest stand that was vulnerable to traffic. Furthermore, we modeled an alternative operation focusing on a ground-based system, addressing the soil vulnerability by considering manual felling, processing, and use of a combi-forwarder for extraction. In the cable-based system, yarding productivity was high (20.3 m3ub/PMH15) due to several reasons, such as a high share of larger dimension timber, the fact that heavy timber was partially de-limbed and processed motor-manually in the stand, the fact that a mini forestry crawler was used for pre-winching the material and finally due to the experience of the operators. Resulting costs for harvesting and extraction were on average €27.8/m3ub. In the ground-based system, costs were on a comparable level (€28.30/m3ub). In our case, the application of a cable yarder in flat terrain was a good alternative and should be considered in future forest management to support environmentally friendly operations and allow independent planning of the operation.
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Tavankar, F., B. Majnounian et A. E. Bonyad. « Felling and skidding damage to residual trees following selection cutting in Caspian forests of Iran ». Journal of Forest Science 59, No. 5 (30 mai 2013) : 196–203. http://dx.doi.org/10.17221/53/2012-jfs.
Texte intégralRésumé :
The felling and skidding damage to residual trees was investigated in a selectively cutting operation in the Caspian forest of Iran. The logging operation was performed by chainsaw and cable skidder. Prelogging, after felling and skidding operations residual tree injuries (species, DBH and damage) were inventoried by systematic plot sampling. Two types of tree damage were observed: destroyed and injured. In this study felling operations mainly injured trees whereas skidding was the main cause of destruction. The percentage of destroyed and injured residual trees by felling operations was 1.4% and 3.4%, whereas the percentage of destroyed and injured residual trees by skid­ding operations was 5.2% and 11.1%. About 87% of destroyed trees were found in the DBH class smaller than 22.5 cm. Maple and Alder were the most damaged trees among the other trees species. Damage to the lower bole and wood damaged intensity were the most common type of injury. To reduce the stand damage, skid trails should be planned before felling and felling directions should be predetermined. In the selection cutting management, limiting logging damage to residual trees must therefore remain a major objective.
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Santos, Paulo Amaro Velloso Henriques dos, Arinei Carlos Lindbeck da Silva, Julio Eduardo Arce et Andrey Lessa Derci Augustynczik. « A Mathematical Model for the Integrated Optimization of Harvest and Transport Scheduling of Forest Products ». Forests 10, no 12 (4 décembre 2019) : 1110. http://dx.doi.org/10.3390/f10121110.
Texte intégralRésumé :
The costs related to forest harvesting and wood transport are key to the economic viability of forest investments. These operations compose a major share of the total cost of wood production and thus need to be conducted in an efficient manner. In this paper, we propose a novel optimization model to tackle this issue and perform the daily and weekly plan of harvesting operations, in order to minimize the costs related to the machinery operation, movement, and wood transportation, subject to demand constraints. Our results show that transportation costs dominate the total cost of these operations. The model proposed is appropriate and can be effectively applied to optimize the operational planning of harvesting activities. Nevertheless, instances with a large number of stands may lead to a substantial increase in the complexity and computational burden. We conclude that operations research techniques can provide a solid basis for decision-making in harvest scheduling problems and increase the efficiency of forest management.
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Trethewey, Diane. « Development of an index for quick comparison of helicopter costs and benefits ». International Journal of Wildland Fire 16, no 4 (2007) : 444. http://dx.doi.org/10.1071/wf06108.
Texte intégralRésumé :
A helicopter comparison index was developed to incorporate cost and benefit information for individual helicopters for large wildland fire suppression operations. The costs and benefits for individual helicopters are unique. Costs consist of daily availability and hourly flight rates. Benefits depend on the payload, which depends on the altitude and temperature of operation, weight of the helicopter, equipment on board, crew, and fuel. Because of the complexity of calculating payload, previous methods for deploying helicopters classified helicopters into three types according to their typical payload. The least expensive helicopter of the desired type was deployed. Because this classification system produces a broad range of benefits within each helicopter type, this method may not deploy the most efficient helicopter. The helicopter comparison index can be calculated at representative altitudes and temperatures before it is needed. As the work is done beforehand, the helicopters can be compared quickly when they are needed. The helicopter comparison index allows helicopters to be compared based on the efficiency of the individual helicopters rather than just their cost of operation. Evaluation of Type I helicopters shows that using the helicopter comparison index instead cost of operation has savings potential of 20 to 45 percent.
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Machado, Jelvis Santos, Stanley Schettino, Fernando Colen et Sidney Pereira. « ERGONOMIC EVALUATION OF AGRICULTURAL TRACTORS USED IN FORESTRY OPERATIONS ». REVISTA ENGENHARIA NA AGRICULTURA - REVENG 28 (11 décembre 2020) : 435–45. http://dx.doi.org/10.13083/reveng.v29i1.8834.
Texte intégralRésumé :
The objective of this work was to evaluate farming machines adapted to forestry work and to verify if their characteristics meet the safety, ergonomics and working conditions necessary to maintain the health and safety of the operators. Thus, three farming tractors were selected, with a closed cabin and a minimum power of 73.5 kW, a widely used specification in the forestry sector. The following ergonomic parameters were considered: acess to the cab, cab dimensions, visibility, seat, controls and operation, work posture, cabin air conditioning, noise, lighting and maintenance aspects. The evaluations were based on the guidelines contained in the “Ergonomic Guidelines for Forest Machines” of the Swedish Forestry Research Institute, developed for forestry machines. The results showed that all the evaluated machines presented ergonomic standards below those indicated in all evaluated aspects, particularly related to access to the work station and difficulties during mechanical maintenance, besides the necessity of adopting forced postures during the working day due to operator’s seats. It was concluded that the farming machines adapted for work in forest processes presented significant gaps in relation to the ergonomic aspects, which represents high and imminent risks of development of occupational diseases in their operators, as well as the predisposition to work accidents.
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Miyajima, Ricardo Hideaki, Paulo Torres Fenner, Gislaine Cristina Batistela et Danilo Simões. « Effect of Feller-Buncher Model, Slope Class and Cutting Area on the Productivity and Costs of Whole Tree Harvesting in Brazilian Eucalyptus Stands ». Forests 12, no 8 (15 août 2021) : 1092. http://dx.doi.org/10.3390/f12081092.
Texte intégralRésumé :
The operational productivity and costs of tree felling operations can be influenced by several factors, among which, the machine characteristics, slope class, the cutting area and the individual volume of the trees stand out. Thus, the main objective of the present study was to analyze the productivity and production cost for two feller-bunchers with different technical characteristics operating in a eucalyptus forest. The productivity was calculated from a time study and the factors analyzed were two feller-buncher models, two slope classes, and two cutting areas. The machine cost per scheduled hour was based on the methodology of the Food and Agriculture Organization of the United Nations. Analysis of the results showed that the felling and turn operational elements occupied the most time in the operational cycle of feller-bunchers. The machine cost per scheduled hour was USD 69.69 h−1 for feller-buncher 1 and USD 102.03 h−1 for feller-buncher 2. In conclusion, the distinct technical characteristics of feller-bunchers were found to influence the productivity and, consequently, the cost, of the felling operation during the harvesting of whole eucalyptus trees.
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Schönauer, Marian, Stephan Hoffmann, Joachim Maack, Martin Jansen et Dirk Jaeger. « Comparison of Selected Terramechanical Test Procedures and Cartographic Indices to Predict Rutting Caused by Machine Traffic during a Cut-to-Length Thinning Operation ». Forests 12, no 2 (20 janvier 2021) : 113. http://dx.doi.org/10.3390/f12020113.
Texte intégralRésumé :
Timber harvesting operations using heavy forest machinery frequently results in severe soil compaction and displacement, threatening sustainable forest management. An accurate prediction of trafficability, considering actual operating conditions, minimizes these impacts and can be facilitated by various predictive tools. Within this study, we validated the accuracy of four terramechanical parameters, including Cone Index (MPa, Penetrologger), penetration depth (cm, Penetrologger), cone penetration (cm blow−1, dual-mass dynamic cone penetrometer) and shear strength (kPa, vane meter), and additionally two cartographic indices (topographic wetness index and depth-to-water). Measurements applying the four terramechanical approaches were performed at 47 transects along newly assigned machine operating trails in two broadleaved dominated mixed stands. After the CTL thinning operation was completed, measurement results and cartographic indices were correlated against rut depth. Under the rather dry soil conditions (29 ± 9 vol%), total rut depth ranged between 2.2 and 11.6 cm, and was clearly predicted by rut depth after a single pass of the harvester, which was used for further validations. The results indicated the easy-to-measure penetration depth as the most accurate approach to predict rut depth, considering coefficients of correlation (rP = 0.44). Moreover, cone penetration (rP = 0.34) provided reliable results. Surprisingly, no response between rut depth and Cone Index was observed, although it is commonly used to assess trafficability. The relatively low moisture conditions probably inhibited a correlation between rutting and moisture content. Consistently, cartographic indices could not be used to predict rutting. Rut depth after the harvester pass was a reliable predictor for total rut depth after 2–5 passes (rP = 0.50). Rarely used parameters, such as cone penetration or shear strength, outcompeted the highly reputed Cone Index, emphasizing further investigations of applied tools.
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Airoldi, Gianfranco, Angela Calvo et Marco Manzone. « Oil Consumption in 4WD Farm Tractors Used in Forestry Operations ». Croatian journal of forest engineering 41, no 2 (8 avril 2020) : 333–45. http://dx.doi.org/10.5552/crojfe.2020.668.
Texte intégralRésumé :
Farm tractors are still widely used in many forestry operations. Predicting fuel and lubricant costs is difficult because their consumption depends on a number of factors such as hours worked and operations performed. Fuel and lubricant consumption is important since it can have an impact at both the economic and environmental level. Many fuel models have been studied in the last decades, but few studies have focused on oil consumption. The ASABE (American Society of Agricultural and Biological Engineers) Standard suggested a model for predicting engine oil consumption of farm tractors of the 1980s, which are potentially different from modern tractor engines. In addition, the recent widespread application of semi- and full-power-shift and continuous variable transmissions and the high number of hydraulic applications increased the amount of lubrication oil for transmission and hydraulic systems.For these reasons, we analysed 133 4WD recent model farm tractors used in forest operations with the aim to study:Þ engine, transmission and hydraulic system oil capacitiesÞ engine oil change intervals as recommended by the manufacturers.A new equation for engine oil consumption, as a function of the rated engine power, was first used and statistically analysed. It was similar to the equation developed by other authors (with a mean difference of 28%, decreasing to 11% at the highest engine power), but well below the ASABE model (with an average engine oil consumption three times higher). Another equation of total oil consumption related to the rated engine power was then studied and compared with a recent study. The results showed an average difference of 18%, decreasing to 8% at the highest engine power. The differences, due to a different machine dataset (only 4WD farm tractors that can be used for forestry operations were analysed) are, however, minimal also in the engine oil consumption model if compared with the oldest ones: a new proposal is therefore necessary, with new and affordable models for correctly evaluating economic and environmental forestry operation costs when using farm tractors.
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Soman, Harikrishnan, Anil Raj Kizha, Bethany Muñoz Delgado, Laura S. Kenefic et Keith Kanoti. « Production economics : comparing hybrid tree-length with whole-tree harvesting methods ». Forestry : An International Journal of Forest Research 93, no 3 (25 janvier 2020) : 389–400. http://dx.doi.org/10.1093/forestry/cpz065.
Texte intégralRésumé :
Abstract Felled trees with tops and branches are transported to the landing with a grapple skidder in conventional ground-based whole-tree (WT) harvesting. This method has greater potential to damage advance regeneration than those in which trees are processed at-stump. Hybrid tree-length (Hyb TL) harvesting using an stroke-boom delimber for in-woods processing might be a feasible alternative, but little is known about the production economics of this method. An experimental strip-cutting study was conducted in central Maine, US in the winter of 2018 to: (1) evaluate and compare operational productivity and costs of ground-based Hyb TL and WT methods; (2) identify factors influencing productivity of at-stump and at-landing log processing; and (3) calculate best management practice (BMP) implementation costs in WT harvesting. Time-motion data were recorded for operational phases such as felling, extraction, processing, sorting and loading; machine rates were calculated to determine productivity and costs of operations. Total cost of Hyb TL (US $17.01 m−3) was lower than that of WT ($18.38 m−3). Processing cost was lower at-stump than at-landing ($2.66 and $2.73 m−3 for Hyb TL and WT, respectively). This is likely due to fewer logs handled per cycle at-landing (1.2 logs per turn) compared to the number handled per cycle at-stump (1.4 logs per turn). Sensitivity analysis showed that a 30-m increase in average in-woods distance travelled by the delimber would result in a 41 per cent increase in the processing cost. Cost of BMP implementation in WT was $2.25 m−3 or $59.2 per productive machine hour. Results suggest that it is feasible to apply Hyb TL method in an industrial harvesting operation, though distance of in-woods delimber movement influences processing costs. Insights from this study will help forest managers and loggers efficiently plan and execute harvesting operations.
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Wibowo, Sarwo Eddi, et Muhammad Zaini. « IMPLEMENTASI KEBIJAKAN PENGELOLAAN HUTAN PRODUKSI LESTARI DI KALIMANTAN TIMUR ». Research Journal of Accounting and Business Management 3, no 2 (31 décembre 2019) : 201. http://dx.doi.org/10.31293/rjabm.v3i2.4428.
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The Natural Production Forest Management (NPFM) policy in East Kalimantan has led to massive deforestation and degradation of East Kalimantan’s natural forests. Until 2012, almost 70% of East Kalimantan,s natural forest production has been damaged, more than that 80% of East Kalimantan,s forestry business has gone bankrupt. While the ecological and social losses are not countless. This is inseparable form the weaknesses in the NPFM policy operating system. In the perspective of administrative science, the effectiveness of NPFM policy implementation is related to the six administrative principles (Max Weber) in NPFM policy. The six neglected administrative principles are : 1) The principle of specialization of organizational functions, resulting in overlapping organizational functions Bureaucracy, Corporations and Operations in NPFM operation; 2) the formal hierarchical structure principle, as result there is no NPFM tiered supervision system; 3) Priciple of formal rules and standard operating prosedures (SOP), as a result, the NPFM deviation since the process of licensing, implementation and distribution of results; 4) Impersonal relationships, as a result bureaucratic decisions tend not to be objective; 5) The principle of special competence (professional), consequently the NPFM operation results are not optimal; 6) The principle of employing is in accordance with competence, consequently the NPFM performance is poor.
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Choudhari, S. A., M. A. Kumbhalkar, D. V. Bhise et M. M. Sardeshmukh. « Optimal reservoir operation policy determination for uncertainty conditions ». 3C Empresa. Investigación y pensamiento crítico 11, no 02 (29 décembre 2022) : 277–95. http://dx.doi.org/10.17993/3cemp.2022.110250.277-295.
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In recent years, optimising reservoir operations has emerged as a hot topic in the field of water resources management. Heuristic approaches to reservoir operation that incorporate rule curves and, to some extent, operator discretion have been the norm in the past. With so many stakeholders involved in water management, it can be difficult to strike a happy medium between everyone's needs and wants. The dissertation proposes a method for transforming traditional reservoir operation into optimal strategies, allowing users to take advantage of the rapid development of computational techniques. This research creates and applies a Multi Objective Fuzzy Linear Programming (MOFLP) model to the monthly operating policies of the stage-I Jayakwadi reservoir located on the Godavari, the largest river in the Indian state of Maharashtra. In order to formulate the problem, we use two objective functions—maximizing irrigation releases and maximising power production releases. The constraints of the study are considered, including turbine release, irrigation demand, reservoir storage capacity, and continuity of reservoir storage. Utilizing linear membership functions, the objective functions are fuzzily defined. All other model parameters except for the goals are assumed to be hard and fast rules. Maximum Happiness Operating Policy (MOFLP) was used to determine the best course of action.
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Orlovský, Lukáš, Valéria Messingerová et Zuzana Danihelová. « Analysis of the time efficiency of skidding technology based on the skidders ». Central European Forestry Journal 66, no 3 (24 août 2020) : 177–87. http://dx.doi.org/10.2478/forj-2020-0016.
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Abstract The time efficiency and principles of ergonomics related to timber skidding are based on the time consumption per work cycle as well as on the time consumption per individual work operations. Regarding the demands on the environmental requirements and ever increasing cost of work, it is necessary to objectively evaluate the inevitable time consumption required for timber skidding using all technologies. The paper summarised the results of time studies for skidder technologies. The time study compares the time consumption and productivity of cable skidders and cable-grapple skidders, with the main focus on developing time prediction models. The main aim of the study was to objectify the skidder time consumption and establish the impact of production factors on the time consumption of partial work operations of skidders. Within the time study 231 work cycles were measured, and 53 snapshots of work day with using methods continual time study. The overall time consumption of the work cycle and gross production rate of the monitored cable and cable-grapple skidders is affected by the following production factors: the skidding distance, volume of skidded logs and number of skidded logs. The impact of individual production factors on the overall time consumption of the work cycle is different for each group of skidders. Non-operation times of the skidder operators’ shifts represent 24.6% with the highest part taken by the technical operation of the work place. The mean gross production rate of the monitored skidders varied from 33.3 to 6.91 m3 h−1.
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Sokolov, A. P., A. A. Seliverstov, Yu V. Sukhanov et V. A. Senkin. « Ergonomic evaluation of forestry crane partial automation system ». FORESTRY BULLETIN 27, no 1 (février 2023) : 139–52. http://dx.doi.org/10.18698/2542-1468-2023-1-139-152.
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Harvesters and forwarders are the main part of cut-to-length logging system equipment. Perfection of the hydraulic cranes have a very large impact on the overall operating efficiency of these forest machines. An analysis of impact of the John Deere crane partial automation option «Intelligent Boom Control» (IBC) on the work cycle and workload of forest machines operators is described in this article. Two machines equipped with IBC systems were studied in field conditions. Differences in frequency and duration of telescopic extension boom control activations were identified. It was determined that as a result of automation, one of the degrees of freedom of the crane controls is practically completely excluded from use in the case of forwarder (decrease by about 10 times). A significant reduction in the duration of its use is observed in the case of harvester (decrease by about 2 times). As a result, this saves the psycho-physiological resources of the operator for more efficient use of remaining degrees of freedom, which, coupled with a simpler and more intuitive logic of the controls operation, improves the productivity, accuracy and safety of cut-to-length logging. In addition, a simpler work algorithm reduces the level of stereotyping of the operator’s actions, fatigue and loss of attention, which usually come out at the end of the shift.
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Shouxian, Du. « The operation method of ultra-low-volume spraying with airplane ». Journal of Northeast Forestry University 7, no 1 (mars 1996) : 48–50. http://dx.doi.org/10.1007/bf02843056.
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Tsushima, Toshiyuki, Ichiro Watanabe, Nobuhiro Akashi et Kenichi Ozaki. « Productivity and Cost of Retention Harvesting Operation in Conifer Plantations ». Forests 14, no 2 (6 février 2023) : 324. http://dx.doi.org/10.3390/f14020324.
Texte intégralRésumé :
Retention forestry is a harvesting system that intentionally retains important forest structures at harvest time. We examined the effect of dispersed retention on the productivity and cost of harvesting operations in a large-scale field experiment in conifer plantations in Hokkaido, Japan. For dispersed retention, we retained broad-leaved trees in three levels (10, 50, or 100 trees/ha). We used daily operator reports and investigated time consumption (h/m3) of felling and pre-hauling operations and the total cost to roadside. Compared with clearcutting, mean felling time was 7% and 17% longer, and mean pre-hauling time was 20% and 19% longer in 50 and 100 retained trees/ha, respectively. The other operations were not affected by tree retention because they were conducted at pre-existed strip roads or landings where no trees were retained. Increased time consumption caused an increased cost of felling and pre-hauling. Compared with clearcutting, the combined cost of felling and pre-hauling was 14% and 18% higher in 50 and 100 retained trees/ha, respectively. However, the total cost to roadside increased only by 3% compared with clearcutting because these two operations in total occupied 19% of the overall cost, and the cost of the other operations was not affected by tree retention. This suggests that the impact of tree retention on the total cost was small and that the harvesting system used in the present study can reduce cost increment due to tree retention unless trees are not retained on strip roads.