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Full-Text Articles in Physics

Intelligent Feature Selection Techniques For Pattern Classification Of Time-Domain Signals, Corey Alexander Miller Jan 2013

Intelligent Feature Selection Techniques For Pattern Classification Of Time-Domain Signals, Corey Alexander Miller

Dissertations, Theses, and Masters Projects

Time-domain signals form the basis of analysis for a variety of applications, including those involving variable conditions or physical changes that result in degraded signal quality. Typical approaches to signal analysis fail under these conditions, as these types of changes often lie outside the scope of the domain's basic analytic theory and are too complex for modeling. Sophisticated signal processing techniques are required as a result. In this work, we develop a robust signal analysis technique that is suitable for a wide variety of time-domain signal analysis applications. Statistical pattern classification routines are applied to problems of interest involving a …


Applications Of Pattern Classification To Time-Domain Signals, Crystal Ann Bertoncini Jan 2010

Applications Of Pattern Classification To Time-Domain Signals, Crystal Ann Bertoncini

Dissertations, Theses, and Masters Projects

Many different kinds of physics are used in sensors that produce time-domain signals, such as ultrasonics, acoustics, seismology, and electromagnetics. The waveforms generated by these sensors are used to measure events or detect flaws in applications ranging from industrial to medical and defense-related domains. Interpreting the signals is challenging because of the complicated physics of the interaction of the fields with the materials and structures under study. often the method of interpreting the signal varies by the application, but automatic detection of events in signals is always useful in order to attain results quickly with less human error. One method …


Chaotic Scattering In An Open Vase-Shaped Cavity: Topological, Numerical, And Experimental Results, Jaison Allen Novick Jan 2009

Chaotic Scattering In An Open Vase-Shaped Cavity: Topological, Numerical, And Experimental Results, Jaison Allen Novick

Dissertations, Theses, and Masters Projects

We present a study of trajectories in a two-dimensional, open, vase-shaped cavity in the absence of forces The classical trajectories freely propagate between elastic collisions. Bound trajectories, regular scattering trajectories, and chaotic scattering trajectories are present in the vase. Most importantly, we find that classical trajectories passing through the vase's mouth escape without return. In our simulations, we propagate bursts of trajectories from point sources located along the vase walls. We record the time for escaping trajectories to pass through the vase's neck. Constructing a plot of escape time versus the initial launch angle for the chaotic trajectories reveals a …


Mode Locking In A Periodically Forced Integrate-And-Fire-Or-Burst Neuron Model, S. Coombes, R. Owen, Gregory D. Smith Oct 2001

Mode Locking In A Periodically Forced Integrate-And-Fire-Or-Burst Neuron Model, S. Coombes, R. Owen, Gregory D. Smith

Arts & Sciences Articles

The minimal “integrate-and-fire-or-burst” (IFB) neuron model reproduces the salient features of experimentally observed thalamocortical relay neuron response properties, including the temporal tuning of both tonic spiking (i.e., conventional action potentials) and post-inhibitory rebound bursting mediated by the low-threshold Ca2+ current, IT. In previous work focusing on experimental and IFB model responses to sinusoidal current injection, large regions of stimulus parameter space were observed for which the response was entrained to periodic applied current, resulting in repetitive burst, tonic, or mixed (i.e., burst followed by tonic) responses. Here we present an exact analysis of such mode-locking in the integrate-and-fire-or-burst model under …