Metrics for Distribution Similarity Applied to the Bucking to Demand Procedure

In the computerized bucking to demand procedure bucking is done according to a given price list and demand matrix, which defines the demands for different log length-diameter class proportions. To achieve as good a log length-diameter distribution as possible, the computer compares demand and actual output to appropriately direct bucking. A comparison has been made with a variable called distribution level, which, however, is unable to distinguish between error that is close to the optimum log length-diameter class proportion and error that is further away. In addition, the distribution level does not distinguish between log length-diameter classes, even though error in one class can be far more undesirable than in another. In this study, bucking to demand using the distribution level was compared to bucking to value and bucking to demand using the penalty segmented distribution level, squared distribution level, chi-square formula and flexible penalty segmented distribution level. The bucking outcome employing these various techniques was achieved by using a bucking simulator and artificially generated stand and stem data. The results show that the best bucking outcomes were produced by methods with a squared error term, i.e. the squared distribution level, chi-squared formula and flexible penalty segmented distribution level. In addition, it was possible to direct error toward preferred log length-diameter classes without substantial loss in overall goodness of fit

A local DLP-GIS-LP system for geographically decentralized wood procurement planning and decision making.

LP is an important method for allocation of wood inventory stock. It is, for instance, used alone in tactical planning systems, which currently are in wide use at the higher hierarchical level in the functionally decentralized planning of the Finnish forest industry. Unfortunately, LP as a solution method has not been capable of handling spatial data that seem to characterize planning systems in geographical decentralization. In the present study, a GIS was used to assimilate data from different wood procurement functions, to calculate transportation distances and cost figures, and to write the data in ASCII files, which were then used as input for the LP model. Using the experiments and methods of GIS on a planning system developed according to participatory planning, the results of this study suggest that the participatory method was faster than the conventional LP method, when solved using actual data. The participatory method was also capable of providing the same global optimum for a wood allocation problem. The implications of these results for improving operational and tactical planning of wood procurement in Finland are discussed

Productivity and Costs of Harwarder Systems in Industrial Roundwood Thinnings

In several studies, the harwarder has proven to be a more cost-effective wood harvesting system than the traditional two-machine (harvester-forwarder) system, especially when the average stem size of the marked stand is relatively small, the removals per hectare/stand low (i.e. the harvesting site small), and the forwarding distance short. One of the strengths of a harwarder is considered to be the lower relocation costs compared to the two-machine system. The time consumption of harwarder relocations have not, however, been reported in the previous harwarder studies. Metsäteho Oy conducted a follow-up study of harwarders in industrial roundwood harvesting, and also investigated the relocations of harwarders. A total of five – three Ponsse Wisent Dual and two Valmet 801 Combi – harwarders were examined in the follow-up study. The amount of harvested industrial roundwood in the study totalled nearly 30,000 m3. The cost calculations showed that the harwarder system is more competitive than the twomachine system when the average stem size of the marked stand is relatively low, i.e. less than 110–170 dm3. Furthermore, harwarders were the most competitive at low-removal harvesting sites. The proportion of the total working time of harwarders used in relocations between harvesting sites was 2.5%, and the effective relocation time was, on the average, 1.3 hours/relocation. The study results underlined that it makes sense to harvest relatively small-removal and small-diameter thinning stands marked for harvesting with a harwarder while, conversely, it is more worthwhile to harvest sites with larger removals and trees using a two-machine harvester-forwarder system, thereby raising the profitability of forest machine business

Potential Traffic Levels after Increasing the Maximum Vehicle Weight in Environmentally Efficient Transportation System: The Case of Finland

The objective of this research was to study how the maximum vehicle weight (76 t) will affect roundwood transportation in environmentally efficient transportation system. Actual traffic levels were assessed with calculations based on the vehicle configurations (60, 64, 68, and 76 t) a year after the weight limit was raised. Consequences of this change were also assessed for predicted future traffic levels. The reduction in operational vehicle-km was 12.5% (versus a decrease of 9.3% based on the legal weight), though this may underestimate the long-term prediction (26.7%) that will be achieved when the roundwood transportation sector adjusts fully to the higher maximum weight limit. The migration of loads to heavier vehicles did not create any wood harvesting problems for 60, 64 and 68 t vehicle configurations. However, 76 t vehicles were often volume-constrained, so it was harder to achieve the maximum weight. The main operational challenge was pulpwood (3.5 and 4.0 m) when onboard loaders were not available. Based on comparison of roundwood length measurements as an indicator of volume-constraint vehicles, the best practice system is discussed to enable an efficient transportation system for sustainable wood procurement

Modeling Backhauling on Finnish Energy-Wood Network Using Minimizing of Empty Routes

This study introduces a support method to use in modeling backhauling. The method minimizes a truck's on-road driving while empty. The backhauling model is based on a commonly used timber transport allocation model. Here, this model is applied to a simulated energy-wood network. The resulting optimization provides two different delivery plans for two-way transportation: one with a constraint to minimize travel distances when empty and the other without this constraint. By applying the empty-route minimization method, the best return routes for trucks are determined beforehand with fewer alternatives then left to be solved by the backhauling model. The results prove that the method can be used to minimize empty-route driving, but further development of the empty-route minimization method is still needed before it can be used in combination with the optimization of backhauling. Therefore, the effects of empty-route minimization on the transportation distances with respect to stand and hauling alternatives are discussed. In addition, the possibility of increasing the profitability of transportation, through the use of the method to optimize energy-wood backhauling, is also discussed

Development of a wood damage monitoring system for mechanized harvesting

Cut-to-length harvesting is a cost-efficient method of the wood supply chain. However, it risks causing stem damage in the mechanized process of thinning forest stands, thereby reducing the growth and technical quality of the remaining trees, which would then be exposed on the increased vulnerability to fungal diseases. For these reasons, it is critical to support quality monitoring of harvesting machines. One way to support quality monitoring is through the application of machine vision solutions. In this study, the damaged stems were photographed systematically from a strip road. The success of the stem-damage detection was analyzed to determine the relationships between successful detection, stand condition, and the image-processing technique. Statistically meaningful relationships were identified via logistic regression analysis, which can be used in selection of tailored image processing technique. The study indicated that the quality-monitoring system of mechanized harvesting could be improved by an increased focus on developing the multi-view photogrammetry of stem damages according to different stand conditions. Further, refining the machine learning system would support the need to determine accurate image-processing thresholds of the texture of stem damages. Then, the overall proportion of successful stem-damage detections will be 89%. These improvements of the quality monitoring system will provide the efficient thinning process in the sustainable wood supply from forests to forest industry. The implementation of such a system could be much broader, initially under Nordic conditions and then in other countries as well, given that its development takes into considerations the significant calibration factors of local conditions

Attitudes of Small and Medium-Sized Enterprises towards Energy Efficiency in Wood Procurement: A Case Study of Stora Enso in Finland

Stora Enso Wood Supply Finland (WSF) was certified to the ISO 50001 Energy Efficiency Management System standard in 2015. At Stora Enso WSF, the goal is to improve energy efficiency by 4% by 2020 from 2015. Improving the energy efficiency of wood procurement (i.e. logging and timber trucking) enterprises is currently one of the main focus areas for energy efficiency development at Stora Enso WSF. In order to clarify its state-of-the-art in the business of wood procurement enterprises at Stora Enso WSF, logging and timber-trucking entrepreneurs were interviewed in November and December 2017. The survey data consisted of 25 logging and 25 timber-trucking entrepreneurs. The coverage rate of both entrepreneur groups was 73.5% in the survey. The results indicated that timber-trucking enterprises highlight more energy efficiency and fuel efficiency than logging enterprises. For instance, the timber-trucking entrepreneurs underscored more energy efficiency in their acquisition decisions of new vehicles and the greater role of fuel efficiency in the energy-efficient business than logging entrepreneurs during 2016 and 2017. Furthermore, the survey results revealed that logging and trucking enterprises can improve energy efficiency in their business by organizing more energy efficiency education (i.e. economical and anticipated driving training) for their machine operators and truck drivers. There is a positive attitude towards energy efficiency among both logging and timber-trucking entrepreneurs. This creates a solid background to deepen and continue energy-effective work in the wood supply chain between the enterprises and Stora Enso WSF in the future