Abstract
dc:description.abstractHysteresis, defined as a rate independent memory effect, is a phenomenon that occurs in many physical systems. The effect is sometimes desired, sometimes a nuisance, sometimes catastrophic, but in every case we must understand hysteresis if we are to better understand the system itself. While the study of hysteresis has been conducted by engineers, scientists and mathematicians, the contribution of mathematicians has at times been theoretically sound but impractical to implement. The goal of this work is to use sound mathematical theory to provide practical information on the subject. The Preisach operator was developed to model hysteresis in magnetism. It is based on a continuous linear combination of relay operators weighted by a distribution function μ. A new method for approximating μ in a finite dimensional space is described. Guidelines are given for choosing the “best” finite dimensional space and a “most efficient” training set. Simulated and experimental data are also introduced to demonstrate the utility of this method. In addition, the approximation of singular Preisach measures is explored. The types of singularities investigated are characterized by non-zero initial slopes of reversal curves. The difficulties of finding the “optimal” approximation in this case are detailed as well as a method for determining an approximation “close” to the optimal approximation.
Degree
thesis:*- Name thesis:degree_name
- Ph. D.
- Level thesis:degree_level
- doctoral
- Discipline thesis:degree_discipline
- Mathematics
- Department dc:contributor.department
- Mathematics
- Grantor dc:publisher
- Virginia Tech
- Year dc:date.issued
- 2001
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Joseph, Daniel Scott
- Chair dc:contributor.committeechair
-
- Rogers, Robert C.
- Committee members dc:contributor.committeemember
-
- Rossi, John F.
- Wheeler, Robert L.
- Borggaard, Jeffrey T.
- Beattie, Christopher A.
Subjects
dc:subject × 3Rights
dc:rights- Statement dc:rights
-
- In Copyright
- Licence dc:rights.uri
Identifiers
dc:identifier.*- Dc Identifier Other
- etd-04262001-125037
- OAI identifier oai:identifier
- oai:vtechworks.lib.vt.edu:10919/27295