scholarly journals Productivity and costs modeling for tree harvesting operations using chainsaws in plantation forests, Tanzania

2014 ◽  
Vol 3 (4) ◽  
pp. 464 ◽  
Author(s):  
Dos Santos Silayo ◽  
George Migunga
Keyword(s):  
Cutting Tools ◽  
Timber Harvesting ◽  
Production Costs ◽  
Private Forests ◽  
Productivity Cost ◽  
Plantation Forests ◽  
Unit Costs ◽  
Delay Times ◽  
Unit Of Measurement ◽  
Tree Cutting

With exemption of a few private forests, timber harvesting in most plantation forests in Tanzania is carried out by less skilled and less equipped crews. Newly recruited crews often learn from experienced ones which may not be doing it in the perfect way. Therefore estimation and projecting production and costs becomes a big problem to logging managers. This study was carried out to develop productivity and costs models for chainsaw operators in a learning experiment. The experiments were designed in clear felling operations. Three experiments were set where each crew category was studied using time study and work sampling techniques that involved studying crews before training, after training and after the break at an interval of three months. Descriptive statistics and modelling was performed for each crews performance. Specific crews productivity and costs models have been developed reflecting necessary and unnecessary delay times. Assessment of the production costs show that unit costs decreases with increasing productivity in each unit of measurement of the production rate. It is recommended that productivity and costs for two-man crosscut saw operators be studied and modelled since they are also the main cutting tools used in tree cutting in Tanzania. Keywords: Productivity, Cost, Timber Harvesting, Modelling, Chainsaw, Tanzania.

scholarly journals The Impact of Weather and Slope Conditions on the Productivity, Cost, and GHG Emissions of a Ground-Based Harvesting Operation in Mountain Hardwoods

Forests ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1612
Author(s):  
Sättar Ezzati ◽  
Farzam Tavankar ◽  
Mohammad Reza Ghaffariyan ◽  
Rachele Venanzi ◽  
Francesco Latterini ◽  
...  
Keyword(s):  
Ghg Emissions ◽  
Timber Harvesting ◽  
Operating Conditions ◽  
Production Costs ◽  
Cost Models ◽  
Mixed Stands ◽  
Average Delay ◽  
Productivity Cost ◽  
Steep Slopes ◽  
The Impact

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−1for 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 4.27m−3 for felling and USD 5.35m−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.

scholarly journals Private Forests in Nepal: Status and Policy Analysis

2017 ◽  
Vol 15 (1) ◽  
pp. 120-130 ◽  
Author(s):  
Swoyambhu M. Amatya ◽  
Prakash Lamsal
Keyword(s):  
Present Status ◽  
National Level ◽  
Timber Harvesting ◽  
Lessons Learned ◽  
Private Land ◽  
Private Forest ◽  
Community Forest ◽  
Private Forest Owners ◽  
Forest Owners ◽  
Private Forests

 This paper reviews and analyses the present status of private forests and tenure administration in light of existing legal, policy, and regulatory frameworks in Nepal. Additionally, the present status of private forests, as well as the scenarios of timber harvesting, transportation, marketing, and their administration are thoroughly revised. Provisions regarding forests and trees on private land and their basis are examined and implications are articulated for potential policy improvements for enhanced tenure security. It is shown that robust national-level policies and legal frameworks exist, and that there is an increasing trend of timber flows to markets from private forests over the past five years. However, there is still skepticism, mistrust and fear amongst private forest owners, saw millers, and forest administration that prevents the full use of the bundle of rights that legal and policy provisions have promised. An unusually slow pace of private forest registration, lengthy and multi stage processes for obtaining harvesting and transportation permits, and official bans on important commercial species, among others, are found to be the factors that most hinder the private forest owners’ and tree growers’ interests, and their rights and obligations with respect to the management and use of their private forest resources. It is concluded that a simplified permitting process along with programmatic support would promote and help to grow private forestry and that Nepal’s experience and lessons learned from community forest implementation would be a great asset to move towards this end. Connecting community forest user groups for organised and cooperative action, and mobilising their institutional strength and accumulated funds for pro-farmer technical and regulatory support would allow farmers to intensify tree plantations and forest management. Further steps are required to convince policymakers and secure necessary budgetary support to this end..

scholarly journals Analysis a cutting edge geometry influence on circular saw teeth at the process of crosscutting wood

2009 ◽  
Vol 57 (5) ◽  
pp. 177-182 ◽  
Author(s):  
Ján Kováč ◽  
Milan Mikleš
Keyword(s):  
Cutting Tools ◽  
Measurement Procedure ◽  
Cutting Edge ◽  
Production Costs ◽  
Cutting Process ◽  
Detailed Measurement ◽  
Edge Geometry ◽  
Circular Saw ◽  
Measuring Devices ◽  
Circular Saws

Nowadays, the wood cutting process looks like a technological scheme consisting of several connected and relatively inseparable parts. The crosscutting wood is the most widespread in the process of fo­rest exploitation; it is used at tree exploitation, shortening stems and assortment production. The article deals with the influence of the cutting edge geometry of circular saws on the torque and also on the cutting performance at the crosscutting wood therefore there is the influence on the whole cutting process. In the article there is described detailed measurement procedure, used measuring devices and the process of results analysis. Knowledge of wood crosscutting process and choice of suitable cutting conditions and cutting tools will contribute to decrease production costs and energy saving.

scholarly journals INCORPORATION OF UNCERTAINTY IN TECHNICAL AND ECONOMIC ANALYSIS OF A FELLER-BUNCHER

FLORESTA ◽  
2018 ◽  
Vol 48 (3) ◽  
pp. 403
Author(s):  
Danilo Simões ◽  
Ricardo Hideaki Miyajima ◽  
Rodrigo Petrongari Tonin ◽  
Paulo Torres Fenner ◽  
Gislaine Cristina Batistela
Keyword(s):  
Economic Analysis ◽  
Production Cost ◽  
Probability Distributions ◽  
Operating Cost ◽  
Timber Harvesting ◽  
Production Costs ◽  
P Value ◽  
Strong Positive Correlation ◽  
Technical And Economic Analysis ◽  
Positive Correlation Coefficient

The constant technical and economic analysis of timber harvesting operations is essential and determining, due to the monetary magnitude. Traditionally, these analyses are conducted deterministically, which does not allow obtaining values with probabilities of occurrence. Considering this issue, stochastic models were built in order to analyze the behavior of probabilistic production cost in felling operations with feller-buncher, through the Monte Carlo method. The study was conducted in the Central-West region of the state of São Paulo in a forest of Eucalyptus sp., with six years of age, planted in 3 x 2 m spacing. Technical analysis was based on the study of time and movements, which determined the effective productivity and economy in the hourly operating cost of the feller-buncher and in the production costs of the operation. Due to uncertainties, probability distributions were assigned to these results, which identified the most relevant variables and quantified the probabilities of the production cost. The results demonstrated that the fuel cost had a statistically significant strong positive correlation coefficient ( = 0.91) (p-value < 0.01). The hourly cost, consequently, was directly proportional to the production cost of the operation. The production cost of the operation in flat relief was 18% lower than the production cost of the operation in undulating relief.

Life Prediction of Cutting Tool by the Workpiece Cutting Condition

2011 ◽  
Vol 223 ◽  
pp. 554-563 ◽  
Author(s):  
Noemia Gomes de Mattos de Mesquita ◽  
José Eduardo Ferreira de Oliveira ◽  
Arimatea Quaresma Ferraz
Keyword(s):  
Cutting Tool ◽  
Cutting Tools ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Operating Conditions ◽  
Production Costs ◽  
Depth Of Cut ◽  
Cutting Condition ◽  
Workpiece Material ◽  
The Cost

Stops to exchange cutting tool, to set up again the tool in a turning operation with CNC or to measure the workpiece dimensions have direct influence on production. The premature removal of the cutting tool results in high cost of machining, since the parcel relating to the cost of the cutting tool increases. On the other hand the late exchange of cutting tool also increases the cost of production because getting parts out of the preset tolerances may require rework for its use, when it does not cause bigger problems such as breaking of cutting tools or the loss of the part. Therefore, the right time to exchange the tool should be well defined when wanted to minimize production costs. When the flank wear is the limiting tool life, the time predetermination that a cutting tool must be used for the machining occurs within the limits of tolerance can be done without difficulty. This paper aims to show how the life of the cutting tool can be calculated taking into account the cutting parameters (cutting speed, feed and depth of cut), workpiece material, power of the machine, the dimensional tolerance of the part, the finishing surface, the geometry of the cutting tool and operating conditions of the machine tool, once known the parameters of Taylor algebraic structure. These parameters were raised for the ABNT 1038 steel machined with cutting tools of hard metal.

Notes on Statistics of Manpower Costs and Unemployment in Major Industrial Countries

1971 ◽  
Vol 56 ◽  
pp. 64-69
Author(s):  
F.K. Jones ◽  
S. Hays ◽  
L.F. Campbell-Boross
Keyword(s):  
Production Costs ◽  
Focus Attention ◽  
Competitive Position ◽  
Industrial Countries ◽  
Export Prices ◽  
Unit Costs ◽  
Statistical Series ◽  
World Markets ◽  
Short Run ◽  
The Cost

This note outlines some of the problems in measuring short-run changes in manpower costs and lists some of the statistical series now available for major industrial countries. Information about changes in the cost of labour provides a useful complement to data about export prices for analysis of the development of a country's competitive position. Each type of indicator has its own drawbacks. For example, for some exports prices are set by competitive world markets and a change in competitiveness may take the form of a change in relative profits rather than a change in price. Moreover, there are well-known difficulties in comparing national indices for prices or unit/average values. For production costs per unit of output, too, there are problems of compilation. There are also problems of interpretation, particularly over very short periods, because the measures can be very erratic. In the field of unit costs it has become usual to focus attention on changes in manpower costs, variously defined, partly because such costs are the most important, and partly because costs of materials (to the extent that they are set by world prices) tend to move more closely in line as between different countries.

scholarly journals Productivity and Costs of Two Beetle-Kill Salvage Harvesting Methods in Northern Colorado

Forests ◽  
2018 ◽  
Vol 9 (9) ◽  
pp. 572 ◽  
Author(s):  
Hee Han ◽  
Woodam Chung ◽  
Ji She ◽  
Nathaniel Anderson ◽  
Lucas Wells
Keyword(s):  
Timber Harvesting ◽  
Production Costs ◽  
Cost Models ◽  
Northern Colorado ◽  
Salvage Harvesting ◽  
Whole Tree Harvesting ◽  
Harvesting Costs ◽  
Tree Method ◽  
Whole Tree ◽  
Tree Harvesting

Two ground-based timber harvesting methods have been commonly used for beetle-kill salvage treatments after a bark beetle epidemic in northern Colorado. A “lop and scatter” method uses a mobilized stroke delimber to delimb and buck trees at the stump, leaving tree tops and limbs on the forest floor, while a whole-tree harvesting method brings the entire tree to the landing where it is delimbed and bucked, and thus produces logging residue piles at the landing as a byproduct. We conducted a detailed comparative time study of the two harvesting methods to develop productivity and cost models and compared the performance of the two methods under various site conditions. We applied the productivity and cost models to lodgepole pine forest stands totaling 3400 hectares of the Colorado State Forest State Park to estimate salvage harvesting costs for each forest stand and identify the least costly harvesting options. The results show that the estimated stump-to-truck timber production costs were $30.00 per oven dry ton (odt) for lop and scatter and $23.88 odt−1 for the whole-tree method in our study harvest unit. At the forest level, the estimated average stump-to-truck costs were $54.67 odt−1 and $56.95 odt−1 for lop and scatter and whole-tree harvesting, respectively. Skidding distance and downed trees affect the harvesting costs of both methods, but their influence appears to be more significant on the whole-tree method.

Optimization Design of the Odometer Gear Pair

2013 ◽  
Vol 734-737 ◽  
pp. 2655-2658
Author(s):  
Yong Xiang Li ◽  
Wen Quan Shen ◽  
You Jia Zhao ◽  
Xiu Yang Hu
Keyword(s):  
Sharp Increase ◽  
Optimization Design ◽  
Production Efficiency ◽  
Cutting Tools ◽  
Production Costs ◽  
Gear Pair ◽  
Theoretical Significance ◽  
Cost Of Production ◽  
The Cost

As to a large variety of the speed ratios of the odometer gear installed on every kind of transmission assembly, the cutting tools of different kinds have also increased, resulting in a sharp increase of the production costs. This paper puts forward an effective method based on the optimization design of the odometer driving gear in order to improve the production efficiency of the odometer gear and then to reduce the cost of production, which has theoretical significance value to some extent for the dynamics optimization design of the odometer gear pair.

scholarly journals Role of the Tennessee Master Logger Program in Implementation of Best Management Practices on Non-Industrial Private Forests

2003 ◽  
Vol 27 (1) ◽  
pp. 36-40 ◽  
Author(s):  
Chad T. Davis ◽  
Wayne K. Clatterbuck
Keyword(s):  
Best Management Practices ◽  
Management Practices ◽  
Field Evaluation ◽  
Timber Harvesting ◽  
Private Forests ◽  
Percentage Score ◽  
Best Management ◽  
Streamside Management Zones ◽  
The Mean ◽  
Private Forestland

Abstract A field evaluation of Best Management Practices (BMPs) was used to determine the effectiveness of the Tennessee Master Logger Program (TMLP) in 1997–1998. The study was conducted on non-industrial private forestland (NIPF) and excluded harvests on land owned by forest industry or public forests. Completed logging jobs were evaluated in relation to four components of timber harvesting: (1) haul roads, (2) skid trails, (3) log decks, and (4) Streamside Management Zones (SMZs). The scores assigned during evaluation to each of the four components were added together to yield an overall score. An overall percentage score was calculated because some sites did not have all four components, for example, SMZs are not necessary on sites without streams. Of 191 randomly chosen logging sites across the state of Tennessee, 38, or 19.9%, were harvested by trained Master Loggers. A significant association (P < 0.05) was found between overall percentage score and logger training. The mean overall percentage score for Master Loggers was 75.1%, and the mean score for untrained loggers was 60.4%. Only 17 of the 627 possible scores or 2.6%, exhibited threats to water quality. Of these 17, Master Loggers were only responsible for 3. Point biserial correlations indicated that a substantial association (P < 0.05) existed between harvests completed by Master Loggers and the scores of haul roads, skid trails, log decks, and SMZ grades. This study indicates that loggers who received training from the TMLP were more likely to implement BMPs during harvesting operations on NIPF than loggers who did not participate in the Tennessee Master Logger Program. South. J. Appl. For. 27(1):36–40.

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