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Speaker Verification In The Presence Of Channel Mismatch Using Gaussian Mixture Models, Robert B. Reid
Speaker Verification In The Presence Of Channel Mismatch Using Gaussian Mixture Models, Robert B. Reid
Theses and Dissertations
A channel compensation method is sought for use in speaker identification (ID) and verification applications under matched and mismatched training and testing conditions. This work expands on previous work on matched conditions by investigating three techniques on matched and mismatched conditions using the TIMIT and NTIMIT speech databases. First, previous results on 168 speakers are reproduced for matched conditions using Gaussian mixture models (GMM) and mel-frequency cepstral coefficients. Next, cepstral mean subtraction with band limiting (CMSBL) is investigated. The third method, developed in this thesis uses a modified Wiener filtering approach to channel compensation. New GMMs are created for each …
Reactive Quantum Scattering In Two Dimensions, Roy S. Calfas
Reactive Quantum Scattering In Two Dimensions, Roy S. Calfas
Theses and Dissertations
In an effort to develop a more efficient time dependent approach for calculating scattering matrix elements, absorbing boundary conditions are combined together with the channel packet method. As an introduction to scattering, scattering matrix elements are presented for a one-dimensional square well and a one-dimensional potential consisting of a Gaussian well with symmetric Gaussian barriers. Next, the combination of the channel packet method together with absorbing boundary conditions yields an order of magnitude savings in the time necessary to compute the correlation function for the collinear H+H
Visualization And Animation Of A Missile/Target Encounter, Jeffrey T. Bush
Visualization And Animation Of A Missile/Target Encounter, Jeffrey T. Bush
Theses and Dissertations
Existing missile/target encounter modeling and simulation systems focus on improving probability of kill models. Little research has been done to visualize these encounters. These systems can be made more useful to the engineers by incorporating current computer graphics technology for visualizing and animating the encounter. Our research has been to develop a graphical simulation package for visualizing both endgame and full fly-out encounters. Endgame visualization includes showing the interaction of a missile, its fuze cone proximity sensors, and its target during the final fraction of a second of the missile/target encounter. Additionally, this system displays dynamic effects such as the …
Effects Of Near-Field Scatterers On Space-Time Adaptive Processing, Jonathan W. Fitton
Effects Of Near-Field Scatterers On Space-Time Adaptive Processing, Jonathan W. Fitton
Theses and Dissertations
Near-field scatterers, such as the wing of an airplane, can affect the ability of the processor to null out clutter and jammer signals. The target, clutter, and jammer signals will reflect off the near-field scatterers into the array and appear to be coming from a direction different from their true sources. This thesis develops a theoretical model for the direct path and scattered path signals from the target, clutter, and jamming signals. The optimum weight vector, normally computed using the steering vector to the target and the covariance matrix of the undesired signals, must now include the effects of the …
Analytic Transfer Function Of The Forward Propagation Of Diffuse Photon Density Waves In Turbid Media With An Embedded Spherical Inhomogeneity, Deborah L. Lasocki
Analytic Transfer Function Of The Forward Propagation Of Diffuse Photon Density Waves In Turbid Media With An Embedded Spherical Inhomogeneity, Deborah L. Lasocki
Theses and Dissertations
Diffusing photons can be used to detect and localize optical inhomogeneities embedded in turbid media such as clouds, fog, paint and human tissue. This thesis shows that a transfer function derived from an analytic solution of the Helmholtz equation can completely characterize in three dimensions the perturbations in the forward propagation phenomena caused by a spherical defect object in a multiple-scattering medium. Two models of the forward propagation behavior of diffuse photon density waves in homogeneous, infinite, turbid media that contains a spherical inhomogeneity are examined. The first model is an exact analytic solution based on a modal expansion in …
A System Dynamics Investigation Of Environmental Attitudes And Behaviors Influencing Solid Waste Reduction, Louis E. Lilley
A System Dynamics Investigation Of Environmental Attitudes And Behaviors Influencing Solid Waste Reduction, Louis E. Lilley
Theses and Dissertations
The relationship between attitudes and behavior is investigated in regard to the reduction of solid waste in a community. The theory of reasoned action, as identified by Ajzen and Fishbein in 1975, is investigated using as system dynamics approach. The closed loop system structure that would produce the expected real world response is established. The structure is then translated into a flow diagram and coded into a mathematical model. The model quantifies the values of beliefs, attitudes, intentions, behaviors, external and demographic variables, perceptions, and waste generation levels in order to illustrate how each changes over time when influenced by …