A problem of interest to forest managers is the optimum arrangement of truck roads and landings for economical logging operations.
This problem becomes more complex if,a combined yarding and swinging
operation is considered. I,t is possible to formulate a mathematical
model to express the cost per unit volume for a...
A model (called MERLIN) is presented that can allow the resource manager to consider the combined effects of silvicultural treatments and their effect on expected logging production and costs. This integrated analysis takes place within the framework of personal computer software readily available to most managers. This integration is accomplished...
An extension of the sensitivity analysis of linear programming, called parametric programming is used in determining optimal sawtimber logging system mix. The five logging systems under study are manual log-length, system, log-length processor and harvester systems, manual tree-length system and tree-length harvester system. In conditions where it is not exactly...
LOCCOST is an interactive computer program that
predicts stump to mill logging costs, stumpage and net
present value of a harvest based on stand data, pond value
and logging parameters, entered by the user. The program is
intended for use by foresters to evaluate the economics of
different stand management...
Strip thinning is recognized as a way of commercial thinning
young-growth stands. strip thinning has been used worldwide. The
purpose of this study was to explicitly evaluate the costs and benefits
associated with skyline strip thinning in young Douglas-fir
(Pseudotuqo menzesii Franco) stands in the Pacific Northwest and to
compare...
The transportation of wood and biomass resources from landing and other collection locations to processing and distribution sites is a substantial cost within the wood supply chain. These high costs provide a basis for research aimed at improving biomass transportation planning decisions and potentially reducing biomass transportation costs. Chip vans...
There is much interest in the State of Vermont in cable harvesting. Since there are no time studies available for cable harvesting with various machines in Vermont, it is necessary to arrive at production and cost levels by a different method.
The method chosen for this paper is made up...
This paper discusses the development of a computer simulation program for the operation of a log landing for the proposed Helistat airship. The first part of the paper describes the time study used to develop production rates for the chasers, buckers, front-end loaders, and skidders to be used on the...
The focus of this research is to develop a personal computer based simulation model of the mechanized logging process, from felling until the log arrives at the sawmill. The SLAM II simulation language is used for modeling, and the main emphasis is on the overall performance of this system, and...
This paper shows how ten easy-to-use linear skyline thinning production rate equations were obtained by transforming existing but more cumbersome turn time equations using the THIN simulation model [11). The equations provide reasonable approximations of delay-free hourly production for several cable yarders operating skyline thinnings under a variety of conditions....
A model is presented which predicts the net present
value of a stand level multi-entry harvest plan. The model
accounts for potential volume losses due to harvest-related soil compaction. The goal of this project was to answer five economic questions about the issue of soil compaction in forestry. The five...
This paper describes the analysis of data from a three-year gross time study of skyline, balloon, and helicopter yarding systems operating in Western Oregon. Data collection activities were designed and supervised by the Pacific Northwest Forest and Range Experiment Station, U.S.D.A. Forest Service. The specific logging systems studied were running...
This paper describes the analysis of data from a three-year gross time study of skyline, balloon, and helicopter yarding systems operating in Western Oregon. Data collection activities were designed and supervised by the Pacific Northwest Forest and Range Experiment Station, U.S.D.A. Forest Service. The specific logging systems studied were running...
The objective of this paper is to develop a methodology for determining running skyline yarder performance based on the mechanical characteristics of the yarder and its interaction with the load and the terrain. A code for implementing this procedure on the HP-9020 will be prepared .
Potentially large savings can be realized within the forest industry by improved machine scheduling, labour scheduling, machine investment, inventory management, and the maximization of wood value. Forecasting must change within the forest industry from Ttguesstimatesll to more efficient production forecasting models. Much work needs to be done with data collection...
Designing timber harvesting units is a challenging task. The task requires decision making on logging equipment, landing site, cable road profile, road location, and transportation system. Traditionally forest planners have done the task manually. However, the manual method makes it difficult to examine many alternatives and the harvest plans depend...
A program was developed on a desktop computer to determine the cable tensions and position of a balloon tethered by two or more guylines. The program was specifically applied to the analysis of the static load lifting capability of the Pendulum Swing Balloon System. This system uses a tethered balloon...
A method is presented in this study for improving
empirical travel cost analyses when truncated data are
available. The analysis expands upon a Monte Carlo study
conducted by Riyadi (1993) which compared the coefficient
and consumer surplus estimates for five travel cost
estimators using both truncated and censored data. Riyadi...
New types of exchange arrangements are becoming
increasingly popular for a wide range of goods traded
internationally. Several types of countertrade
arrangements have been identified, ranging from pure
barter to more elaborate schemes where only a portion of
the trade is "paid for" in goods, including bilateral
trading agreements with...
Contract harvest operations have become the preferred approach to reducing the largest cost component of timber production through free market competition amongst logging contractors bidding or negotiating for work. The goal of this research was to investigate economic components of harvesting operations not previously studied for steep slope thinning harvests...
A computer program package to estimate cable yarding
payload capability was made. The package was intended to
expand applicability of existing packages and to be user
friendly. It has six system options: live skyline, standing
skyline, running skyline, slackline, multispan and highlead.
In the standing skyline and multispan analyses, load...
This work describes the modeling framework and initial results for CLAWS (Coupled
Landscape And Water System), a physically-based, spatially-distributed hydrologicgeomorphic model that has been coupled with a vegetation dynamics simulation. Spatial variability of topography, soil, vegetation, and climate drive a hydrology module that calculates the water budget at given time...
This paper studies the problem of learning diagnostic policies from training examples. A diagnostic policy is a complete description of the decision-making actions of a diagnostician (i.e., tests followed by a diagnostic decision) for all possible combinations of test results. An optimal diagnostic policy is one that minimizes the expected...
An analysis of forces on two tree intermediate supports is presented. The analysis is in two parts:
The maximum force that the support jack will experience. The movement and forces created in the two tree support by the skyline and carriage. The maximum force on the support jack occurs when...
The algorithm RLS-PLUS was developed to yield solutions to the
multivariate control problem of diameter and species optimization for mixed conifer
and hardwood stands. The problem is specified with twenty-five state variables
consisting of five species groups with four merchantable diameter classes and one
unmerchantable class. This gives twenty diameter...
Volume I: TREES (Timber Resource Economic Estimation System), a forest management and harvest scheduling model, is comprehensively described in the first of a four-volume series. Even- or uneven-aged forest inventories form basic resource units (BRUs), entered by age class or size and diameter classes; stocking level; and management intensity. Management...
Objective of this study was to compare accuracy of
several travel cost methods, by employing Monte Carlo
simulations in the single site framework. Estimates from
five methods were compared to the "true" travel cost
coefficient and "true" consumer surplus. Each method was
ranked, using the root mean squared error (RMSE)...
The Elliott State Forest, located in the Coast Range of Oregon, is currently revising their Habitat Conservation Plan (HCP). Many of the constraints in the HCP are spatial, requiring identification of specific parcels in order to limit activity along habitat reserves, limit harvest opening size, and to coordinate activities within...
This dissertation is a collection of three manuscripts that serve to fill the knowledge gaps and advance methods of detecting the effects of contemporary forest harvesting in experimental catchment studies. While there is a preponderance of studies evaluating the environmental effects of forest harvesting in the western United States, few...