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Ice shape characterization using self-organizing maps
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Kreeger, Richard E. Tino, Peter McClain, Stephen T. |
| Copyright Year | 2011 |
| Description | A method for characterizing ice shapes using a self-organizing map (SOM) technique is presented. Self-organizing maps are neural-network techniques for representing noisy, multi-dimensional data aligned along a lower-dimensional and possibly nonlinear manifold. For a large set of noisy data, each element of a finite set of codebook vectors is iteratively moved in the direction of the data closest to the winner codebook vector. Through successive iterations, the codebook vectors begin to align with the trends of the higher-dimensional data. In information processing, the intent of SOM methods is to transmit the codebook vectors, which contains far fewer elements and requires much less memory or bandwidth, than the original noisy data set. When applied to airfoil ice accretion shapes, the properties of the codebook vectors and the statistical nature of the SOM methods allows for a quantitative comparison of experimentally measured mean or average ice shapes to ice shapes predicted using computer codes such as LEWICE. The nature of the codebook vectors also enables grid generation and surface roughness descriptions for use with the discrete-element roughness approach. In the present study, SOM characterizations are applied to a rime ice shape, a glaze ice shape at an angle of attack, a bi-modal glaze ice shape, and a multi-horn glaze ice shape. Improvements and future explorations will be discussed. |
| File Size | 2853930 |
| Page Count | 19 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20110012461 |
| Archival Resource Key | ark:/13960/t4zh1mr1x |
| Language | English |
| Publisher Date | 2011-05-01 |
| Access Restriction | Open |
| Subject Keyword | Aerodynamics Neural Nets Aircraft Icing Airfoils Iteration Mapping Surface Roughness Computer Programs Characterization Algorithms Bandwidth Vectors Mathematics Shapes Angle of Attack Grid Generation Mathematics Manifolds Mathematics Ntrs Nasa Technical Reports ServerĀ (ntrs) Nasa Technical Reports Server Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |