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Two cable logging systems were reviewed to compare the efficiency of potential biomass extraction from remote forest sites in Ireland based on productive machine hour (PMH) and unit cost of operation (€/m3). Three operational scenarios (SC) were analysed where SC I was a three man crew operation (choker setter, the carriage operator and unhooking c...
Contexts in source publication
Context 1
... summary of the data collection is outlined in Table 3 followed by Table 4 detailing the results of the time study with recorded times and standard deviations for the six major work elements of the study. The hauling out/in and pulling out/in activities are effectively the same. ...
Context 2
... from the observed sites of this study include 3.50, 4.01 and 4.77 min for total cycle time of cable logging operations in Ireland. Comparing the figures from Table 3 suggests operations in Ireland are comparative to previous studies in other countries, if not better (Figure 11). Baker et al. [9] stated that between 10% and 20% of the total cycle time can be attributed to unhooking the chokers at landing. ...
Citations
... Also the influence of various silvicultural treatments Han 2001, 2008;Hoffmann et al. 2016b;Erber et al. 2017), different operational parameters such as the yarding direction (Spinelli et al. 2015;Lee et al. 2018), or the extraction method (Cho et al. 2019; Han and Han 2020) were surveyed. Aspects of ergonomic improvement such as the usage of radio-controlled chokers (Leitner 2009;Stampfer et al. 2010;Devlin and Klvac 2014) or the possibilities of indulgent silvicultural treatment for especially sensitive environments (Schweier and Ludowicy 2020;Shoshyn et al. 2022) are motives to investigate cable yarding operations as a part of the wood supply chain. Table 1 provides a description of the purposes of the reviewed studies. ...
... The start of the "choker setting" (Ghaffariyan et al. 2010), "choking" (Jeong et al. 2017), "choke" (Talbot et al. 2013) or "hook-up" (Hoffmann et al. 2016b) cycle element is in most cases marked by the arrival of the choker setter with the hook at the load, or when the choker setter starts to attach the first piece of wood (Devlin and Klvac 2014). It ends when the choker setter is in the clear and gives the sign, respectively (Baek et al. 2020). ...
Cable yarding is a well-established practice for wood extraction in mountainous regions in most parts of the world where fully mechanized harvesting systems like harvester-forwarder combinations cannot operate due to steep terrain. Work- and time-studies are most relevant to create productivity models for cost estimation, simulation, system development or simply to compare different harvesting systems. The present work investigates 70 work studies on cable yarding operations, regarding assessment methods to establish a knowledge base on cable yarding performance models. A comprehensive literature research was performed to identify relevant studies. Information about the investigated extraction campaigns regarding site specifics, stock specifics, the utilized equipment alongside the work-study-methods, as well as the statistical approaches for model creation were collected. The data gained and the associated models were systematically analyzed to compare different yarding systems concerning their performance. A set of 98 models was selected for this purpose. Productivity of the investigated systems ranges from 1.5 m³/PSH to 69.3 m³/PSH with a mean value of 9.8 m³/PSH where PSH represents the productive system hour. A meta-analysis was performed with the data that is presented in the literature found to test several hypotheses concerning the influence of different parameters on the performance of yarding systems. Various relationships are so strong that regression analysis with the meta-dataset, that is mostly containing mean values presented, results in significant correlations. The diversity in problem formulation and the corresponding diversity in methodical approaches account for limitations in comparability of performance. The consultation of guiding literature on forest work studies can promote comparability between studies.
... It is supposed that this system will be more effective than the modern cable yarders, because of no lateral yarding and manual work associated with load movement. Therefore, the time consumption is reduced as well as the number of yarding crews (Devlin, Klvač 2014). ...
The article proposes new technological techniques for clear cutting in swampy areas using standing skylines, new construction of yarder and the technology of its operation. As a result of the research on using the Larix 3T-500 cable yarder in winter and summer, the operational negative peculiarities of tower yarder in waterlogged forests were identified. Analysing data on experimental comparative time studies, some measures to reduce the negative effect of the identified features on yarding, felling, lateral yarding were worked out. General recommendations for work performance in swampy logging areas were developed. Based on the initial data for each bundle (yarding distance, lateral yarding distance, average volume of the bundle, etc.) the calculation in the MathCad program was performed and a regression dependence of the yarder performance was obtained. Obtained numerical data on comparative time studies of the working cycle operations were summarized in bar charts, taking into account the loss of time on operations.
... Assessing enterprises' TIC is to judge the potential leader and competitiveness in a given technology field using a set of valuable indexes [6], which is helpful for managers in formulating the strategy and direction of technology development [7]. A company with a muscular TIC may continuously conduct technology innovation activities and create much technological superiority and competitive advantages in markets [8,9]. However, evaluating enterprises' TIC is challenging due to the uncertainty and inaccuracy of technical innovation-related activities, which has attracted the great attention of academia. ...
Technological innovation capability (TIC) refers to a fundamental ability owned by an organization to invest and reorganize production factors in technology innovation for gaining competitive advantages. It has attracted increasing attention to evaluate enterprises’ TIC in a competitive market. However, the existing methods have some limitations in the accuracy and efficiency of assessing TIC. This paper proposes a novel approach of evaluating enterprises’ TIC, which combines the entropy weight method and Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) based on patent information. Entropy can determine the weights of indicators that help improve the rationality of the weighting. Besides, TOPSIS may reasonably rank the calculating results, which helps solve poor results in a fuzzy comprehensive evaluation. The paper takes seven enterprises in the solar cell technology field as samples to illustrate the proposed method. The results show that the Entropy-TOPSIS method can effectively evaluate enterprises’ TIC and is more suitable for small samples.
... Studies of technical and infrastructural solutions to wood mobilisation in the Irish forest sector have also been conducted (e.g. Devlin and McDonnell, 2008;Devlin and Klvač, 2014;Sosa et al., 2015;Rivera and Nieuwenhuis, 2018). While technical solutions are important, research must not only develop silvicultural technologies but must also reflect on how readily adoptable these technologies are on the ground and evaluate the actual contribution of adoption (Lawrence, 2018). ...
In the face of growing demand for sustainable sources of biomass, the challenge of mobilising non-industrial private forest landowners (NIPF) with varying management objectives, to actively manage their forests and increase the supply of wood biomass, is an area of growing research and policy focus. While innovation and knowledge exchange is increasingly viewed as a means of promoting sustainable wood mobilisation, structural weaknesses in the sector such as deficiencies in the institutional and infrastructural setting or capacity of stakeholders, can negatively influence innovation processes. Addressing these overarching challenges requires a systemic analysis of the barriers to innovation across the forest sector as a whole. This case study of the Irish forest sector develops a comprehensive innovation systems framework, integrating structural and functional streams of innovation systems research. This `coupled structural–functional’ framework is applied to identify a number of interconnected systemic problems that hinder the functioning of the forest sector innovation system and negatively influence the potential for co-innovation and wood mobilisation in the sector. Three sets of key systemic wood mobilisation problems are identified, among which there is negative feedback. These so called `blocking mechanisms' have developed over time as a result of historical patterns of practice, prevailing culture, attitude and regulation and are defined here as (i) weak networks blocking capacity development of new forest owners, (ii) infrastructural problems blocking the reach and effectiveness of knowledge networks, (iii) rigid institutional structures and policy blocking co-innovation. To address these deficiencies in the current forest policy and institutional environment, this study makes a number of policy recommendations to promote co-innovation and tackle the multi-dimensional challenge of wood mobilisation.
... • Unit costs; comparison with other products • Volume • Potential uptake Devlin and Klvač (2014), Spinelli et al. (2014b) Forestry inputs such as advice and markets. These studies are summarized in Table 4. ...
Forests are expected to contribute towards an increase in supply of sustainable renewable materials and energy, which is commonly referred to as ‘wood mobilization’. In Europe, much attention has focused on the gap between wood potentially and actually harvested. This paper assesses the evidence for successful interventions, based on a critical review of evidence conducted through the EU-funded project SIMWOOD (Sustainable Innovative Mobilisation of Wood). Few evaluations are able to report the impact of interventions on the amount of wood harvested in a way that can be attributed unambiguously to the intervention. The review concludes that (1) there is a need to focus less on surveys of constraints and more on real-life interventions and their success or otherwise; (2) more could be learnt from the experience of such interventions, if evaluations were published in the scientific literature, and if qualitative methods were included, to help understand why stakeholders do or do not change behaviours and increase wood harvests; (3) successful interventions are multifaceted (often combining incentives and advice, or farming and forestry, or production and markets) and (4) although experience can be shared effectively between regions, interventions must be tailored to local social, biophysical and political conditions and developed in context.
... The use of an excavator as the base for the grapple yarder offers significant benefits-especially global availability, ease of operation, versatility, relatively low cost, and robustness [41]. Further, the large mass of the excavator base and the use of the boom as an outrigger allow the guylines to be dispensed with [42]. In turn, un-guyed yarders offer the main advantage of quick repositioning, which allows cost-effective operation in short corridors and reduction of corridor spacing, to the benefit of minimizing the need for time-consuming and potentially high-impact lateral yarding [43]. ...
New techniques have recently appeared that can extend the advantages of grapple yarding to fast-growing plantations. The most promising technique consists of an excavator-base un-guyed yarder equipped with new radio-controlled grapple carriages, fed by another excavator stationed on the cut-over. This system is very productive, avoids in-stand traffic, and removes operators from positions of high risk. This paper presents the results of a long-term study conducted on 12 different teams equipped with the new technology, operating in the fast-growing black wattle (Acacia mangiumWilld) plantations of Sarawak, Malaysia. Data were collected continuously for almost 8 months and represented 555 shifts, or over 55,000 cycles-each recorded individually. Production, utilization, and machine availability were estimated, respectively at: 63 m³ per productive machine hour (excluding all delays), 63% and 93%. Regression analysis of experimental data yielded a strong productivity forecast model that was highly significant, accounted for 50% of the total variability in the dataset and was validated with a non-significant error estimated at less than 1%. The figures reported in this study are especially robust, because they were obtained from a long-term study that covered multiple teams and accumulated an exceptionally large number of observations.
... The daily work productivity varied from 34.144 m³ to 62.976 m³ for different yarding distance up to maximum 600 m in these studies at the region [14][15][16][17][18][19][20][21]. It was found that the daily productivity and operational cost varied from 19.2 to 74.4 m 3 m 3 respectively at other studies were made on European countries [8,[32][33][34][35][36][37][38][39][40][41][42]. The results of the cost analysis show that the configuration gives average values according to the recent studies. ...
The skyline yarder usage is the main extraction system in developed countries especially on steep terrains depending on cost effectiveness. Despite the availability of skyline yarder in many different types and characteristics it is extremely important choosing the feasible skyline yarder that will best meet the wood extraction requirements of any particular forest area, whether it is purchased or manufactured. It was aimed to configure the feasible forest skyline yarder by determining the technical and economic characteristics, which will be needed according to the qualifications of wood extraction operations of the Eastern Black Sea region of Turkey. The configuration is based on determining the technical specifications (skyline cable length, max. cycle load capacity and daily productivity) of the skyline yarder according to the extraction distance and the carrying capacity to be determined depending on the load to be carried at carriage cycle time. Technical specifications were evaluated by the cost of skyline yarder operation and the cost of the alternative extracting system by cost-effectiveness analysis method. The study showed that a feasible skyline yarder's technical specification must have at least 700 m yarding distances, ten cycles per a working day and 2.2 t carriage load capacity per cycle. This skyline yarders can be operated at the cost of 16.70 €m3 if the daily productivity amount 30 m3 is. The work machine companies produce in a wide range of technical specifications, for this reason, the feasibility analysis should be made for selection of a logging machine, especially for local usage. Also, if domestic machinery production is considered, this scientific data will be the starting point.
... Yoshimura and Noba (2013) note that the highlead configuration is prevalent in Japan. Other countries with a documented use of excavator-based yarders are Ireland (Devlin & Klva c, 2014), Scotland (Tuer, Saunders, & MacIntosh, 2013), Canada (Gingras, 2013) and South Africa (McEwan, Brink, & van Zyl, 2013). Some of the advantages of excavator based yarders over conventional truck based units are (i) that guying is usually not necessary as the mass of the base machine itself provides enough ballast to counteract the forces in the cable, (ii) that the non-guyed machine is mobile on the landing and can move aside to allow passage of timber trucks in narrow confines, or move when space becomes confined due to a shortage of timber trucks (iii) that excavators are relatively cheap and commonly available base machines with seasonal demand in agriculture or road construction and maintenance, and (iv) it is relatively easy to switch between yarding and excavator functions (Talbot, Tarp, & Nitteberg, 2014). ...
(free download http://authors.elsevier.com/a/1R1ew5Tbkjuodc ) An assessment of the benefits of a fully integrated yarder-processor was made against the alternative of splitting the yarding and processing functions onto two base machines. The effect of productivity rates, specific costs, and crew sizes on the relative performance of each working configuration was investigated. The systems analysis showed that for the integrated yarder machine, a two-man crew was considerably cheaper than a three-man crew at all yarding distances, although the difference became less pronounced with increasing mean tree volumes. The single integrated machine with a 2-man crew was cheaper than the modelled 2-machine system at medium and longer extraction distances, as the processor base machine in the 2-machine systems incurred a considerable cost penalty in waiting idly for the yarder. At shorter distances (75 m) the 2-machine system was cheapest, but became less competitive with increasing mean tree volume. For mid-sized trees (0.38 m3) on a medium corridor length of 150 m, overall system productivity rates ranged from 5.2 m3 per productive system hour (PSH) for the single machine system to 9.4 PSH−1 for the 2-machine system, although the specific net costs were almost identical at 31.5 € m−3. A sensitivity analysis showed that reduced labour costs would promote use of the 2-machine system, suggesting that the optimum system configuration would be country specific. Despite being marginally more costly in small trees at short corridor lengths (75 m), the single fully-integrated machine was considered the working configuration of choice under Norwegian conditions.
Interviews with 51 entrepreneurs indicated that Italian cable-yarding specialist companies are small-scale businesses with a workforce of 3 to 5 operators and an annual production of about 5000 m³ over bark. Their primary piece of equipment is a tower yarder, which relies on a support fleet consisting of adapted farm tractors and excavators. There is a clear divide between alpine and non-alpine entrepreneurs, the latter being less productive and somewhat more versatile than the former. That difference is likely dependent on the different work environment: alpine operators can rely on larger public owners, bigger softwood trees and more valuable timber products, whereas non-alpine loggers are constrained by fragmented private ownerships, smaller hardwood trees (often coppice) and less valuable firewood products. Non-alpine loggers also yard on shorter distances and use smaller towers. Further expansion of cable-logging south of the Alps could be achieved by developing new equipment capable of overcoming those limitations. In that regard, one may consider unguyed towers designed for live skyline operation.
New technological methods of operation of a standing skyline are proposed when yarding wood in swampy conditions. As a result of experimental studies in winter and summer, a full range of operational features of the use of cable yarders in swampy logging areas was identified: multiple contact interactions of a trilled pack of timber with high stumps, timber in an apiary, groundwater discharge to the surface of a logging area, and etc. A technology for the development of cutting areas with the help of standing skyline, based on the technology of work of standing skyline, has been proposed. New methods of felling, under-drifting and yarding were proposed for the main technology. The main principle of the developed techniques is in the felling of trees in such a way that they are skidded without contact with the supporting trees and anchors of the intermediate support. Depending on the location of the pack, several options for working methods are offered: moving the pack bypassing the anchors or between the anchor and the supporting tree; turning the butts until they coincide with the axis of the skidding corridor or partially pulling the pack in the direction opposite to the main direction of skidding with subsequent movement along the skidding corridor.
