Using cointegration analyses, we examined the econometric relationship between the US exports of selected forest products (roundwood, sawnwood, and paper and paper board) and a group of microeconomic factors. Overall, we found a positive impact of economic growth of importing countries on total US export of forest products, but mixed results for exchange rate risk and relative price by model specifications, by exchange rate risk measures, and across forest products.Abstract
The market efficiency of the US forest industry had evolved over the past decade. In this study, the entropy measurement, an econophysic approach, was applied to quantify the informational efficiency of timber real estate investment trusts (REITs), wood, furniture, and paper markets in the United States during the period from 1999 to 2012. In a relative context, indices on Treasury bonds were used to proxy the risk-free rate of returns, while Standard & Poor's (S&P) 500 stock returns were used as a yardstick for risky investments. The analysis indicated that the forest markets were considerably more informationally efficient than the Treasury market. Furthermore, most markets were marginally more efficient compared with the S&P 500 index, with the exception of REIT returns. Therefore, better arbitrage opportunities were present in REIT investments.Abstract
Our objective was to describe the trends of Vermont stumpage prices for major sawtimber species and products over the approximately last quarter century and propose a likely explanation of changes that we observed. Annual percentage rates of change (APR) were estimated for 10 forest products in Vermont from the third quarter of 1981 (1981Q3) to the first quarter of 2007 (2007Q1) when the price series was discontinued. In addition, we tested for changes in the percentage rate within the period. We found differences in the trend of APR between hardwood sawtimber and softwood sawtimber. With one exception, price trends differed significantly between 1981Q3 to 1992Q2 and 1992Q3 to 2007Q1 for inflation-adjusted (real) hardwood sawtimber prices. There were no differences in price trends for any of the softwood sawtimber species between the two periods. Real price trends for pulpwood and firewood were similar to those for hardwood sawtimber. We also examined stumpage price trends for selected species in adjacent New Hampshire from 1985Q1 to 2011Q1. Stumpage price trends for like species and proximate time periods in Vermont and New Hampshire were similar, but no statistical tests were done. The direction of trend (positive or negative) was the same for sugar maple, red oak, yellow birch, and white pine, and the magnitude of APR was similar for sugar maple, yellow birch, and white pine.Abstract
Accurate and timely product costing information is critically important for companies in planning the optimal utilization of company resources. While an overestimation of product costs can lead to loss of potential business and market share, underestimation of product costs can result in financial losses to the company. This article introduces a product costing program called WoodCite that was specifically developed for small and medium-sized hardwood dimension and components manufacturers. WoodCite is a Microsoft Access application that allows companies to determine product costs and to create competitive bids based on their company and product information. The program uses a regression model to estimate the overhead cost of a product based on historical cost information provided by the user. WoodCite was developed with input from members of the Wood Components Manufacturers Association. The application is available for free at Virginia Tech's Wood Products Web site (http://woodproducts.sbio.vt.edu/woodcite).Abstract
User needs relating to products are expressed in the language of customers. Designers are facing the challenge of answering the question of how relatively subjective customer needs can be translated into precise target specifications. In most cases, some of these needs can be interpreted as ergonomic requirements. This is especially true for furniture. The question is what a piece of furniture has to do to bring about satisfaction in use. Ergonomic suitability has a number of components, each of which is determined by a given set of product properties. Therefore, ergonomic quality can be satisfied by using complex methods of analysis. Such methods include Quality Function Deployment (QFD). The adaptability of this methodology for the ergonomic design of seats was confirmed as a result of our study. Furthermore, it has been found that the components of ergonomic quality can be treated as dependent variables. The level of these dependent variables is determined by quantitative and categorical product-related independent characteristics. A model for evaluating and designing ergonomic quality on the basis of the method of Design of Experiments was conceived as a complement to the QFD-based approach and is demonstrated for sitting furniture.Abstract
Roundwood scanners utilizing X-ray computed tomography (CT) provide the information required for individual log-sawing optimization. However, errors in the automated detection of quality-relevant internal wood features for sawing control may lead to improper log positioning at breakdown, impairing the realization of value recovery potential. It is thus of interest to have an estimation of the impact of feature detection errors on the performance of sawing optimization. A sensitivity analysis was conducted to quantify the effect of errors in knot detection on a breakdown optimization by adjustment of log rotation. Therefore, sawing simulations were performed with the geometric descriptions of log shape and internal knots extracted from the CT scans of 57 Norway spruce (Picea abies (L.) Karst.) logs. Three types of artificially set knot description errors were tested under different pricing and product scenarios, each in different magnitudes as systematic or random error. Errors in knot diameter were found to have the greatest impact for both systematic and random errors. The effect of errors in dead knot border radial position was less pronounced but still substantial for higher error levels, while errors in knot rotational position could be neglected even for the highest magnitudes of error tested. The assumed price differentiation between product qualities had a major influence on the impact of the errors. It could be observed that with errors of higher magnitudes than those reported for present knot detection algorithms, an improvement in value recovery compared with outer-shape–based optimization still resulted in the simulated rotation optimization.Abstract
The extent of boron penetration in framing lumber treated by spray applications during construction is not well quantified. This study evaluated the effect of formulation and concentration on diffusion of boron in lumber specimens that were equilibrated in conditions that produced wood moisture contents of 18 to 21 percent. One set of specimens was pressure treated with water before equilibration. Borate solutions were prepared from powdered disodium octaborate tetrahydrate (DOT) or from two commercial glycol-borate formulations and applied with a garden-type sprayer. The DOT solution was applied at a 15 percent concentration, while the glycol-borate formulations were applied at 15 and 23 percent concentrations. Boron penetration was evaluated after 6, 13, and 26 weeks and boron retention after 26 weeks of diffusion. Boron penetration was observed for all treatments and progressed for the duration of the study. There was no significant penetration difference between the powdered DOT and glycol-borate solutions when they were applied at the same (15%) DOT concentration. However, after 6 weeks, the glycol-borate solutions applied at the 23 percent DOT concentration produced significantly greater depth of penetration than the solutions applied at the 15 percent concentration. The exception was the 15 percent DOT solution applied to the specimens that had been wetted and then dried down to equilibrium conditions. These specimens had the greatest penetration, possibly as a result of their higher equilibrium moisture content. Retention analysis revealed that the glycol-borate solutions applied at the 23 percent DOT concentration yielded significantly greater boron retentions in the outer assay zone. This effect was less apparent for the inner assay zones. Although boron retentions in the outer assay zone were below those standardized for pressure-treated wood, in some cases they exceeded reported concentrations needed for protection against termites and decay fungi.Abstract
The main objective of this study was to evaluate the feasibility of using unmodified plastic film as a novel wood adhesive in the plywood production, which is done to eliminate formaldehyde release during plywood production and use. The bondability of plastic film was determined by testing the shear strength of plywood. In addition, physical–mechanical properties, including thickness swelling, water absorption, modulus of elasticity, and modulus of rupture under the optimal pressing conditions, were also considered. Results showed that the plywood could meet the requirements for Grade 2 plywood according to Chinese National Standard (GB/T 17657‐1999) and that the highest strength was obtained under hot-pressing conditions (pressure, 0.7 MPa; temperature, 160°C; time, 1 min·mm−1; and film dosage of two layers), which was comparable to that of commercial urea-formaldehyde plywood as determined by Liu (Master's thesis, Zhejiang Agric. and Forestry Univ., Hangzhou, China, 2010). Pressing temperature had a notable effect on adhesive penetration and bonded joints formed. Mechanical interlock, as observed by scanning electron microscopy, formed between nonpolar plastic film and porous poplar veneer.Abstract
This study examined the antimold effect of ultrasonic treatment on Moso bamboo. Six different ultrasonic processes were conducted, and mold development was observed after 4-week high-humidity conditioning. The results showed that the mold rate of bamboo decreased after ultrasonic treatment, which was inversely proportional to the power and duration of treatment time. Scanning electron microscopic analysis revealed that the starch granules largely disappeared after ultrasonic treatment, which likely occurred because the ultrasonic wave broke or gelatinized the starch and widened the pits of the cell wall so that the starch could easily flow out resulting in slightly reduced mold growth.Abstract