THE DESIGN AND ANALYSIS OF EXPERIMENTS. By Oscar Kempthorne. New York, John Wiley and Sons, Inc., 1952. 631 pp. $8.50. This book by a teacher of statistics (as well as a consultant for \"experimenters\") is a comprehensive study of the philosophical background for the statistical design of experiment. It is necessary to have some facility with algebraic notation and manipulation to be able to use the volume intelligently. The problems are presented from the theoretical point of view, without such practical examples as would be helpful for those not acquainted with mathematics. The mathematical justification for the techniques is given. As a somewhat advanced treatment of the design and analysis of experiments, this volume will be interesting and helpful for many who approach statistics theoretically as well as practically. With emphasis on the \"why,\" and with description given broadly, the author relates the subject matter to the general theory of statistics and to the general problem of experimental inference. MARGARET J. ROBERTSON

The Design and Analysis of Experiments

Engineered mycelium composite construction materials from fungal biorefineries: A critical review

When wood is exposed to elevated temperatures, changes can occur in its chemical structure that affect its performance. The extent of the changes depends on the temperature level and the length of time under exposure conditions. The changes in chemical structure may be manifested only as reduced strength, and hydroscopic water and volatile oil weight loss. In contrast, very drastic chemical changes may result in reduced strength and significant carbohydrate weight loss. At temperatures below 100°C, permanent reductions in strength can occur. The magnitude of the reduction depends on the moisture content, heating medium, exposure period and species. The strength degradation is usually not considered to result from the same thermal decomposition of the wood that occurs above 100°C, since no significant carbohydrate weight loss occurs. The strength degradation is probably due to depolymerization reactions, although little research has been done on the chemical mechanism. Reviews by Gerhards (1979, 1982, 1983) and Koch (1985) summarize reduction in strength at temperatures below 100oC (See Strength). If the wood has been treated with a chemical to reduce its flammability, more significant reductions in strength can occur at lower temperatures than for untreated wood. This is due to the presence of chemicals that catalyze the dehydration and depolymerization reactions. A review by Winandy (1987) summarizes the effects of elevated temperatures on strength properties of treated wood. At temperatures above 100oC, chemical bonds begin to break. The rate at which the bonds are broken increases as the temperature increases. Between 100°C and 200oC, noncombustible products, such as carbon dioxide, traces of organic compounds and water vapor, are produced. Above 200oC the celluloses break down, producing tars and flammable volatiles that can diffuse into the surrounding environment. If the volatile compounds are mixed with air and heated to the ignition temperature, combustion reactions occur. The energy from these exothermic reactions radiates to the solid material, thereby propagating the combustion, or pyrolysis, reactions. If the burning mixture accumulates enough energy to emit radiation in the visible spectrum, the phenomenon is known as flaming combustion (see Fire and Wood). Above 450oC all volatile material is gone. The residue that remains is an activated char that can be oxidized to carbon dioxide, carbon monoxide and water vapor. Oxidation of the char is referred to as afterglow. The thermal degradation of wood can be represented by two pathways (Fig. 1), one occurring at high temperatures (>300oC), the other at lower temperatures. These two competing reactions occur simultaneously. Fire retardants work by shifting degradation to the low-temperature pathway.

태양선택 흡수면의 Thermal Degradation

Effect of accelerated weathering on surface chemistry of modified wood

Inspired by the functional behavior of the biological nervous system of the human brain, the artificial neural network (ANN) has found many applications as a superior tool to model complex, dynamic, highly nonlinear, and ill-defined scientific and engineering problems. For this reason, ANNs are employed extensively in drying applications because of their favorable characteristics, such as efficiency, generalization, and simplicity. This article presents a comprehensive review of numerous significant applications of the ANN technique to solve problems of nonlinear function approximation, pattern detection, data interpretation, optimization, simulation, diagnosis, control, data sorting, clustering, and noise reduction in drying technology. We summarize the use of the ANN approach in modeling various dehydration methods; e.g., batch convective thin-layer drying, fluidized bed drying, osmotic dehydration, osmotic-convective drying, infrared, microwave, infrared- and microwave-assisted drying processes, spray ...

Application of Artificial Neural Networks (ANNs) in Drying Technology: A Comprehensive Review

Surface roughness and color characteristics of wood treated with preservatives after accelerated weathering test

Activation of wood surfaces for glue bonds by mechanical pre-treatment and its effects on some properties of veneer surfaces and plywood panels

Effects of surface inactivation, high temperature drying and preservative treatment on surface roughness and colour of alder and beech wood

Effects of moisture content on formaldehyde emission and mechanical properties of plywood

Laminated Veneer Lumber (LVL) panels made from eucalyptus (Eucalyptus camaldulensis Dehn.) and beech (Fagus orientalis Lipsky.) veneers were tested for physical and mechanical strength properties in this study. Urea formaldehyde (UF) and Polyvinyl acetate (PVA) adhesives were used for eucalyptus LVL panels and UF adhesive for beech LVL panels. The effect of veneer wood species on some physical and mechanical properties was found statistically significant. Also, different glue species caused the differences in strength properties of LVL panels.

A comparative study on some physical and mechanical properties of Laminated Veneer Lumber (LVL) produced from Beech ( Fagus orientalis Lipsky) and Eucalyptus ( Eucalyptus camaldulensis Dehn.) veneers

Ismail Aydin

Papers

Surface roughness and color characteristics of wood treated with preservatives after accelerated weathering test

Activation of wood surfaces for glue bonds by mechanical pre-treatment and its effects on some properties of veneer surfaces and plywood panels

Effects of surface inactivation, high temperature drying and preservative treatment on surface roughness and colour of alder and beech wood

Effects of moisture content on formaldehyde emission and mechanical properties of plywood

A comparative study on some physical and mechanical properties of Laminated Veneer Lumber (LVL) produced from Beech ( Fagus orientalis Lipsky) and Eucalyptus ( Eucalyptus camaldulensis Dehn.) veneers