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Full-Text Articles in Physics
Filtered Noise Can Mimic Low-Dimensional Chaotic Attractors, P. E. Rapp, Alfonso M. Albano, T. I. Schmah, L. A. Farwell
Filtered Noise Can Mimic Low-Dimensional Chaotic Attractors, P. E. Rapp, Alfonso M. Albano, T. I. Schmah, L. A. Farwell
Physics Faculty Research and Scholarship
This contribution presents four results. First, calculations indicate that when examined by the Grassberger-Procaccia algorithm alone, filtered noise can mimic low-dimensional chaotic attractors. Given the ubiquity Of signal filtering in experimental investigations, this is potentially important. Second, a criterion is derived which provides an estimate of the minimum data accuracy needed to resolve the dimension of an attractor. Third, it is shown that a criterion derived by Eckmann and Ruelle [Physica D 56, 185 (1992)] to estimate the minimum number of data points required in a Grassberger-Procaccia calculation can be used to provide a further check on these dimension estimates. …
Dipole-Dipole Spin Relaxation In Solids. The Unrestricted Hopping Model And The Methyl Proton - Non-Methyl Proton Interaction, Christopher Palmer, Alfonso M. Albano, Peter A. Beckmann
Dipole-Dipole Spin Relaxation In Solids. The Unrestricted Hopping Model And The Methyl Proton - Non-Methyl Proton Interaction, Christopher Palmer, Alfonso M. Albano, Peter A. Beckmann
Physics Faculty Research and Scholarship
We report proton Zeeman relaxation rates R as a function of temperature T at 8.5 and 53 MHz in polycrystalline 1,9-dimethylphenanthrene (1,9-DMP) and l-trideuteriomethyl-9-methylphenanthrene (1, 9-DMP[1-d3]). The data are interpreted using a Davidson-Cole spectral density for intramolecular reorientation and the implications of this are discussed. R vs T−1data for 1,9-DMP[1-d3] are used to determine the parameters that characterize the reorientation of the 9-methyl group. By assuming that the parameters characterizing the dynamics of the 9-methyl group are the same in 1,9-DMP and 1,9-DMP[1-d3], we subtract out the R vs T−1 contribution of the 9-methyl group in 1,9-DMP to …