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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Extensions of principal components analysis

Brubaker, S. Charles. January 2009 (has links)
Thesis (Ph.D)--Computing, Georgia Institute of Technology, 2009. / Committee Chair: Santosh Vempala; Committee Member: Adam Kalai; Committee Member: Haesun Park; Committee Member: Ravi Kannan; Committee Member: Vladimir Koltchinskii. Part of the SMARTech Electronic Thesis and Dissertation Collection.
12

Incremental algorithms for multilinear principal component analysis of tensor objects

Cao, Zisheng, 曹子晟 January 2013 (has links)
In recent years, massive data sets are generated in many areas of science and business, and are gathered by using advanced data acquisition techniques. New approaches are therefore required to facilitate effective data management and data analysis in this big data era, especially to analyze multidimensional data for real-time applications. This thesis aims at developing generic and effective algorithms for compressing and recovering online multidimensional data, and applying such algorithms in image processing and other related areas. Since multidimensional data are usually represented by tensors, this research uses multilinear algebra as the mathematical foundation to facilitate development. After reviewing the techniques of singular value decomposition (SVD), principal component analysis (PCA) and tensor decomposition, this thesis deduces an effective multilinear principal component analysis (MPCA) method to process such data by seeking optimal orthogonal basis functions that map the original tensor space to a tensor subspace with minimal reconstruction error. Two real examples, 3D data compression for positron emission tomography (PET) and offline fabric defect detection, are used to illustrate the tensor decomposition method and the deduced MPCA method, respectively. Based on the deduced MPCA method, this research develops an incremental MPCA (IMPCA) algorithm which targets at compressing and recovering online tensor objects. To reduce computational complexity of the IMPCA algorithm, this research investigates the low-rank updates of singular values in the matrix and tensor domains, which leads to the development of a sequential low-rank update scheme similar to the sequential Karhunen-Loeve algorithm (SKL) for incremental matrix singular value decomposition, a sequential low-rank update scheme for incremental tensor decomposition, and a quick subspace tracking (QST) algorithm to further enhance the low-rank updates of singular values if the matrix is positive-symmetric definite. Although QST is slightly inferior to the SKL algorithm in terms of accuracy in estimating eigenvector and eigenvalue, the algorithm has lower computational complexity. Two fast incremental MPCA (IMPCA) algorithms are then developed by incorporating the SKL algorithm and the QST algorithm separately into the IMPCA algorithm. Results obtained from applying the developed IMPCA algorithms to detect anomalies from online multidimensional data in a number of numerical experiments, and to track and reconstruct the global surface temperature anomalies over the past several decades clearly confirm the excellent performance of the algorithms. This research also applies the developed IMPCA algorithms to solve an online fabric defect inspection problem. Unlike existing pixel-wise detection schemes, the developed algorithms employ a scanning window to extract tensor objects from fabric images, and to detect the occurrence of anomalies. The proposed method is unsupervised because no pre-training is needed. Two image processing techniques, selective local Gabor binary patterns (SLGBP) and multi-channel feature combination, are developed to accomplish the feature extraction of textile patterns and represent the features as tensor objects. Results of experiments conducted by using a real textile dataset confirm that the developed algorithms are comparable to existing supervised methods in terms of accuracy and computational complexity. A cost-effective parallel implementation scheme is developed to solve the problem in real-time. / published_or_final_version / Industrial and Manufacturing Systems Engineering / Doctoral / Doctor of Philosophy
13

Trend forecasting of tropical cyclone behaviour using Eigenvector analysis of the relationship with 500 hPa pattern

鄭子山, Cheng, Tze-shan. January 1988 (has links)
published_or_final_version / Geography and Geology / Master / Master of Philosophy
14

Application of chemometric analysis to UV-visible and diffuse near-infrared reflectance spectra

Davis, Christopher Brent. Busch, Kenneth W. Busch, Marianna A. January 2007 (has links)
Thesis (Ph.D.)--Baylor University, 2007. / Includes bibliographical references (p. 225-231).
15

A comprehensive investigation of ambient mercury in the Ohio River Valley source-receptor relationship and meteorological impact /

Gao, Fei. January 2007 (has links)
Thesis (M.S.)--Ohio University, November, 2007. / Title from PDF t.p. Includes bibliographical references.
16

Novel approaches for application of principal component analysis on dynamic PET images for improvement of image quality and clinical diagnosis /

Razifar, Pasha, January 2005 (has links)
Diss. (sammanfattning) Uppsala : Uppsala universitet, 2005. / Härtill 6 uppsatser.
17

Supervised and unsupervised PRIDIT for active insurance fraud detection

Ai, Jing, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.
18

Scheduling optimal maintenance times for a system based on component reliabilities /

Rao, Naresh Krishna, January 1992 (has links)
Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 105-107). Also available via the Internet.
19

A Monte Carlo study of the influence of reliability on four rules for determining the number of components to retain from a principal components analysis /

Kanyongo, Gibbs Yanai. January 2004 (has links)
Thesis (Ph. D.)--Ohio University, March, 2004. / Includes bibliographical references (leaves 129-136).
20

A framework for representing non-stationary data with mixtures of linear models /

Archer, Cynthia, January 2002 (has links)
Thesis (Ph. D.)--OGI School of Science & Engineering at OHSU, 2002.

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