Thesis (M.S.)--Oregon State University, 1973. / Typescript (photocopy). Includes bibliographical references. Also available on the World Wide Web.

The potential gains that could be realized from optimizing timber harvesting are significant. To a great extent it is these initial functions that dictate the quality of future manufacturing steps. Timber harvesting systems are defined by the operations they contain and the equipment that perform them. For any given harvesting situation there are a large number of unique systems, performing under a variety of cost, production, and environmental conditions. The objective of optimized timber harvesting is to reduce cost while simultaneously increasing production and minimizing environmental impact. One way to accomplish this objective is through mechanization and automation. Mechanization increases the production output, efficiency, and product quality. However selecting an appropriate level of mechanization to avoid under utilization of expensive resources is a critical decision. The decision requires that the product mix, environmental and user specified constraints be matched against the available equipment technology, and the required performance criteria. This research describes a computer based system which queries a user on the timber stand specifics and a set of harvesting objectives. The system then matches these user's needs to a level of mechanization that would maximize the efficiency of the production system. The computer accomplishes this by searching a set of databases containing information on the available technology and its impact on production, efficiency, economics and the environment. The level of mechanization is determined by specific combinations of existing equipment. Individual pieces of equipment that are compatible with one another are balanced together to form a viable productive unit. / Graduation date: 1991

Thesis (Ph. D.)--University of Texas at Austin, 1998. / Vita. Includes bibliographical references (leaves 192-194). Available also in a digital version from Dissertation Abstracts.

A survey of thirty-nine (39) industrial forest engineers was conducted to provide guidelines as to what harvesting system is best suited to specific stand and topographic variables when extracting streamside timber. The advantages and disadvantages of the operational characteristics of the standard highlead spar, mini spar, slackline, grapple yarder and rubber tire skidder are discussed both in terms of site disturbance and wood debris in British Columbia Coastal streams. Productivity and cost data are analyzed for the standard highlead spar, grapple yarder and rubber tire skidder for three selected streamside conditions. The extra cost incurred by the forest sector to comply with stream protection measures requested by fisheries personnel for pre and post harvesting treatments is also presented. Findings indicate that specific topographic and timber conditions, plus the limitations of each harvesting system dictate the selection of the system when logging adjacent to small British Columbia Coastal streams. The grapple yarder is shown to be the most cost effective and efficient system for streamside timber harvest and stream debris management. The stump to dump productivities for the highlead spar, grapple yarder and rubber tire skidder are found to differ. For the three terrain conditions cited, the grapple yarder is shown to be most productive, while the rubber tire skidder is the least costly. Stream protection costs for fisheries concerns were found to be a substantial extra cost to the forest sector. Debris clean-up costs in particular, ranged from $3.00 to $15.00 per lineal metre of stream. The recommendations of the survey respondents and current literature all clearly demonstrate that each area to be harvested having fish values must be dealt with on a site specific basis. / Forestry, Faculty of / Graduate

This thesis introduces new software to interactively construct multi-layer models and bedding sequences, populate layer-by-layer properties, and enable the fast simulation of nuclear logs. The method consists of modifying simultaneously layer thicknesses and properties to rapidly simulate the outcome (nuclear logs) for comparison to field logs. I include applications which appraise the numerical simulation of gamma-ray, density, compensated neutron, and photoelectric factor logs. An analogous application for sonic modeling is considered as well which uses a modified version of Wyllie’s slowness averaging equation. The procedure is tested for the case of vertical wells and horizontal layers. Examples of application include 6 synthetic and 5 field cases. Additionally, the software is implemented in combination with other formation-evaluation procedures to interpret resistivity and nuclear logs. Simulations of nuclear logs for synthetic models can be used to improve the assessment and interpretation of field data. Interactive modeling and simulation of nuclear logs provides a very good agreement with field logs with an average error of 3.9%. The order of logs to be matched as well as the data available are significant factors in the accuracy of the match. Numerical simulation and matching of field logs using fast modeling procedures is a reliable method to improve the inference of static and dynamic petrophysical properties of rock formations. / text

The forest products industry often uses intermediate-support cable logging systems to transport logs from the harvest site to a staging area. A method is presented to assist in the analysis and design of these cable systems. The method determines tensions in individual cables, forces on and stresses in the support trees, and the geometry of the system under load. Static equilibrium and cable length compatibility are used to generate a system of simultaneous equations. This system of coupled, non-linear algebraic equations is solved numerically using the Newton-Raphson algorithm. A good, automated initial guess for the unknown quantities, based on the physics of the problem, is provided. A model of an example intermediate support cable logging system is analyzed by the proposed approach and the resulting behavior discussed. The method includes the effects of catenary sag and elastic stretch in the cables, and elastic behavior in the support trees. Friction is ignored in the formulation. The catenary and elastic stretch methodologies for the cables are each demonstrated on a single cable span as well as on a demonstration cable system. The effect of the support tree flexibility and cable mass are found to be significant on the response of the cable logging system. The effects of elastic stretch in the cables is not found to be significant for the cable logging systems considered. / Graduation date: 1997

Thesis (Ph. D.)--Oregon State University, 1997. / Typescript (photocopy). Includes bibliographical references (leaves 161-182). Also available on the World Wide Web.

Thesis--Auburn University, 2009. / Abstract. Vita. Includes bibliographical references.

Thesis (M.S.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 81-86). Also available on the World Wide Web.

Thesis (Ph. D.)--Oregon State University, 2005. / Printout. Includes bibliographical references. Also available on the World Wide Web.