mentary fuzzy set operations. For in stance, the abstracted library spectrum in Figure 8a can be compared with a sample spectrum in Figure 8b by fuzzy intersection. Thus a spectral library search can be performed with a higher matching rate than those of methods
that use conventional similarity or dis tance measures. F u z z y d a t a analysis The uncertainty of experimental ob servations can also be expressed by fuzzy sets. A difference from statistical
Archaeological Wood Properties, Chemistry, and Preservation
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Figure 7. Kosko's Bidirectional Associative Memory (BAM) consisting of the neuron input field F A and output neurons F B interconnected symmetrically by the synapses.
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Specific areas discussed include the chemical composition of wood and changes brought on by the decay process, biopredators, radiation curing, freeze-drying, chemical preservation techniques, museum environments, the ethics of conservation, and value systems for choos ing among the qualities of wood that can be preserved. Contents Scope and History of Archaeological Wood · Structure and Degrada tion, Waterlogged Wood · Structure and Aging, Dry Wood · Physical and Mechanical Properties * Chemistry of Archaeological Wood · Bio logical Degradation of Wood • Treatments for Waterlogged and Dry Wood · Polyethylene Glycol Preservation Method · Radiation-Curing Monomers and Resins «Application of Freeze-Drying Outdoor Wood Weathering and Protection · Consolidation Systems for Degraded Wood • Impregnation With Thermoplastic Resins * Giuing of Archaeo logical Wood * Exhibition and Storage · Chemical Modification of Cell Wall Polymers · New Directions in Conservation
Roger M. Rowell, Editor, U.S. Department of Agriculture R. James Barbour, Editor, Forintek Canada Corporation Developed from a symposium sponsored by the Cellu lose, Paper and Textile Division of the American Chem ical Society Advances in Chemistry Series No. 225 488 pages (1990) Clothbound ISBN 0-8412-1623-1 LC 89-39451 $79.95 Ο · R · D · Ε · R
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Figure 8. Representation of U V spectra in a fuzzy neural network, the adaptive BAM. (a) Spectra recorded under different experimental conditions are stored as fuzzy sets in the neuron fields F A and F B . (b) Crisp sample spectrum presented to the neural network for comparison with the stored fuzzy spectra.
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ANALYTICAL CHEMISTRY, VOL. 62, NO. 14, JULY 15, 1990 · 801 A