Spelling suggestions: "subject:"transforms"" "subject:"ztransforms""
1 
The xray transform /Solmon, Donald C. January 1974 (has links)
Thesis (Ph. D.)Oregon State University, 1974. / Typescript (photocopy). Includes bibliographical references. Also available on the World Wide Web.

2 
Numerical methods for the computation of combustionProsser, Robert January 1997 (has links)
No description available.

3 
TWODIMENSIONAL SIGNAL PROCESSING IN RADON SPACE (OPTICAL SIGNAL, IMAGE PROCESSING, FOURIER TRANSFORMS).EASTON, ROGER LEE, JR. January 1986 (has links)
This dissertation considers a method for processing twodimensional (2D) signals (e.g. imagery) by transformation to a coordinate space where the 2D operation separates into orthogonal 1D operations. After processing, the 2D output is reconstructed by a second coordinate transformation. This approach is based on the Radon transform, which maps a twodimensional Cartesian representation of a signal into a series of onedimensional signals by lineintegral projection. The mathematical principles of this transformation are wellknown as the basis for medical computed tomography. This approach can process signals more rapidly than conventional digital processing and more flexibly and precisely than optical techniques. A new formulation of the Radon transform is introduced that employs a new transformationthe centralslice transformto symmetrize the operations between the Cartesian and Radon representations of the signal and to aid in analyzing operations that may be susceptible to solution in this manner. It is wellknown that 2D Fourier transforms and convolutions can be performed by 1D operations after Radon transformation, as proven by the centralslice and filter theorems. Demonstrations of these operations via Radon transforms are described. An optical system has been constructed to derive the lineintegral projections of 2D transmissive or reflective input data. Fourier transforms of the projections are derived by a surfaceacousticwave chirp Fourier transformer, and filtering is performed in a surfaceacousticwave convolver. Reconstruction of the processed 2D signal is performed optically. The system can process 2D imagery at approximately 5 frames/second, though rates to 30 frames/second are achievable if a faster image rotator is added. Other signal processing operations in Radon space are demonstrated, including Labeyrie stellar speckle interferometry, the Hartley transform, and the joint coordinatefrequency representations such as the Wigner distribution function. Other operations worthy of further study include derivation of the 2D cepstrum, and several spectrum estimation algorithms.

4 
Colour object recognition using a complex colour representation and the frequency domainThornton, A. L. January 1998 (has links)
No description available.

5 
Vibration condition monitoring and fault diagnostics of rotating machinery using artificial neural networksPaya, Basir Abdul January 1998 (has links)
No description available.

6 
Genealogy under fissionfusion models of population subdivisionCurnow, Paula January 2003 (has links)
No description available.

7 
DecimationinFrequency Fast Fourier Transforms for the Symmetric GroupMalm, Eric 01 April 2005 (has links)
In this thesis, we present a new class of algorithms that determine fast Fourier transforms for a given finite group G. These algorithms use eigenspace projections determined by a chain of subgroups of G, and rely on a path algebraic approach to the representation theory of finite groups developed by Ram (26). Applying this framework to the symmetric group, Sn, yields a class of fast Fourier transforms that we conjecture to run in O(n2n!) time. We also discuss several future directions for this research.

8 
A Fast Fourier Transform for the Symmetric GroupBrand, Tristan 01 May 2006 (has links)
A discrete Fourier transform, or DFT, is an isomorphism from a group algebra to a direct sum of matrix algebras. An algorithm that efficiently applies a DFT is called a fast Fourier transform, or FFT. The concept of a DFT will be introduced and examined from both a general and algebraic perspective. We will then present and analyze a specific FFT for the symmetric group.

9 
Sparse signal recovery in a transform domainLebed, Evgeniy 11 1900 (has links)
The ability to efficiently and sparsely represent seismic data is becoming an increasingly important problem in geophysics. Over the last thirty years many transforms such as wavelets, curvelets, contourlets, surfacelets, shearlets, and many other types of ‘xlets’ have been developed. Such transform were leveraged to resolve this issue of sparse representations. In this work we compare the properties of four of these commonly used transforms, namely the shiftinvariant wavelets, complex wavelets, curvelets and surfacelets. We also explore the performance of these transforms for the problem of recovering seismic wavefields from incomplete measurements.

10 
Density conditions on Gabor framesLeach, Sandie Patricia 01 December 2003 (has links)
No description available.

Page generated in 0.063 seconds