Growth Rings

Growth of Graded Noetherian Rings

We show that every graded locally finite right noetherian algebra has sub-exponential growth. As a consequence, every noetherian algebra with exponential growth has no finite dimensional filtration which leads to a right (or left) noetherian associated graded algebra. We also prove that every connected graded right noetherian algebra with finite global dimension has finite GK-dimension. Using t...

Differential Polynomial Rings of Triangular Matrix Rings

The Effects of Lumber Seasonal Growth Rings on Microwave Measurements

In order to determine more accurate indicators of wood structure obtained by microwave sensing and improve our understanding of plane wave propagation through this complex material, we have undertaken a permittivity survey and experimentally investigated scattering of a plane wave, measuring its transmission over two non-parallel surfaces of a rectangular lumber sample. This novel non-destructi...

Polynomial Rings over Pseudovaluation Rings

Let R be a ring. Let σ be an automorphism of R. We define a σ-divided ring and prove the following. (1) Let R be a commutative pseudovaluation ring such that x ∈ P for any P ∈ Spec(R[x,σ]) . Then R[x,σ] is also a pseudovaluation ring. (2) Let R be a σ-divided ring such that x ∈ P for any P ∈ Spec(R[x,σ]). Then R[x,σ] is also a σ-divided ring. Let now R be a commutative Noetherian Q-algebra (Q i...

Growth rings, growth ring formation and age determination in the mangrove Rhizophora mucronata.

BACKGROUND AND AIMS The mangrove Rhizophora mucronata has previously been reported to lack annual growth rings, thus barring it from dendrochronological studies. In this study the reported absence of the growth rings was reconsidered and the periodic nature of light and dark brown layers visible on polished stem discs investigated. In addition, the formation of these layers in relation to preva...