This thesis introduces and explores the notion of a real-world environment with respect to adaptive pattern recognition and neural network systems. It then examines the individual properties of a real-world environment and proposes Continuous Adaptation, Persistence of information and Context-sensitive recognition to be the major design criteria a neural network system in a real-world environment should satisfy. Based on these criteria, it then assesses the performance of Hopfield networks and Associative Memory systems and identifies their operational limitations. This leads to the introduction of Randomized Internal Representations, a novel class of neural network systems which stores information in a fully distributed way yet is capable of encoding and utilizing context. It then assesses the performance of Competitive Learning and Adaptive Resonance Theory systems and again having identified their operational weakness, it describes the Dynamic Adaptation Scheme which satisfies all three design criteria for a real-world environment.

Sustained resonance in a linear oscillator is achievable with a drive whose constant frequency matches the resonant frequency of the oscillator. In oscillators with nonlinear restoring forces, i.e., Dung-type oscillators, resonant frequency changes with amplitude, so a constant frequency drive generates a beat oscillation instead of sustained resonance. Dung-type oscillators can be driven into sustained resonance, called autoresonance (AR), when drive frequency is swept in time to match the changing resonant frequency of the oscillator. It is found that near-optimal drive linear sweep rates for autoresonance can be estimated from the beat oscillation resulting from constant frequency excitation. Specically, a least squares estimate of the slope of the Teager-Kaiser instantaneous frequency versus time plot for the rising half-cycle of the beat response to a stationary drive provides a near-optimal estimate of the linear drive sweep rate that sustains resonance in the pendulum, Dung and Dung-Van der Pol oscillators. These predictions are confirmed with model-based numerical simulations. A closed-form approximation to the AM-FM nonlinear resonance beat response of a Dung oscillator driven at its low-amplitude oscillator frequency is obtained from a solution to an associated Mathieu equation. AR time responses are found to evolve along a Mathieu equation primary resonance stability boundary. AR breakdown occurs at sweep rates just past optimal and map to a single stable point just off the Mathieu equation primary resonance stability boundary. Optimal AR sweep rates produce oscillating phase dierences with extrema near 90 degrees, allowing extended time in resonance. AR breakdown occurs when phase difference equals 180 degrees. Nonlinear resonance of the van der Pol type may play a role in the extraordinary sensitivity of the human ear. / The mechanism for maintaining the cochlear amplifier at its critical point is currently unknown. The possibility of open-loop control of cochlear operating point, maintaining criticality on average through periodically varying damping (super-regeneration) motivates a study of spontaneous otoacoustic emission (SOAE) amplitude modulation on a short (msec) time scale. An example of periodic amplitude modulation within a wide filter bandwidth is found that appears to be a beat oscillation of two SOAEs. / by Carey Witkov. / Thesis (Ph.D.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.

University of Macau / Faculty of Science and Technology. / Department of Computer and Information Science

University of Macau / Faculty of Science and Technology. / Department of Computer and Information Science

by Cheung Wai-Hung Wellis. / Thesis (M.Sc.)--Chinese University of Hong Kong, 1992. / Includes bibliographical references (leaves 52-54). / ACKNOWLEDGEMENTS / ABSTRACT / Chapter 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- CLASSIFICATION OF CHARACTER RECOGNITION --- p.1 / Chapter 1.2 --- HISTORICAL DEVELOPMENT --- p.3 / Chapter 1.3 --- RECOGNITION METHODOLOGY --- p.4 / Chapter 2 --- ORGANIZATION OF THIS REPORT --- p.7 / Chapter 3 --- DATA SAMPLING --- p.8 / Chapter 3.1 --- GENERAL CONSIDERATION --- p.8 / Chapter 3.2 --- IMPLEMENTATION --- p.9 / Chapter 4 --- PREPROCESSING --- p.10 / Chapter 4.1 --- GENERAL CONSIDERATION --- p.10 / Chapter 4.2 --- IMPLEMENTATION --- p.12 / Chapter 4.2.1 --- Stroke connection --- p.12 / Chapter 4.2.2 --- Rotation --- p.12 / Chapter 4.2.3 --- Scaling --- p.14 / Chapter 4.2.4 --- De-skewing --- p.15 / Chapter 5 --- STROKE SEGMENTATION --- p.17 / Chapter 5.1 --- CONSIDERATION --- p.17 / Chapter 5.2 --- IMPLEMENTATION --- p.20 / Chapter 6 --- LEARNING --- p.26 / Chapter 7 --- PROTOTYPE MANAGEMENT --- p.27 / Chapter 8 --- RECOGNITION --- p.29 / Chapter 8.1 --- CONSIDERATION --- p.29 / Chapter 8.1.1 --- Delayed Stroke Tagging --- p.29 / Chapter 8.1.2 --- Bi-gram --- p.29 / Chapter 8.1.3 --- Character Scoring --- p.30 / Chapter 8.1.4 --- Ligature Handling --- p.32 / Chapter 8.1.5 --- Word Scoring --- p.32 / Chapter 8.2 --- IMPLEMENTATION --- p.33 / Chapter 8.2.1 --- Simple Matching --- p.33 / Chapter 8.2.2 --- Best First Search Matching --- p.33 / Chapter 8.2.3 --- Multiple Track Method --- p.35 / Chapter 8.3 --- SYSTEM PERFORMANCE TUNING --- p.37 / Chapter 9 --- POST-PROCESSING --- p.38 / Chapter 9.1 --- PROBABILITY MODEL --- p.38 / Chapter 9.2 --- WORD DICTIONARY APPROACH --- p.39 / Chapter 10 --- SYSTEM IMPLEMENTATION AND PERFORMANCE --- p.41 / Chapter 11 --- DISCUSSION --- p.43 / Chapter 12 --- EPILOG --- p.47 / Chapter APPENDIX I - --- PROBLEMS ENCOUNTERED AND SUGGESTED ENHANCEMENTS ON THE SYSTEM --- p.48 / Chapter APPENDIX II - --- GLOSSARIES --- p.51 / REFERENCES --- p.52

Lam, Hiu Man. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 143-148). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese.

Hui, Ka Yu. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 101-106). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese.

Data sets with rich topical structure are common in many real world text classification tasks. A single data set often contains a wide variety of topics and, in a typical task, documents belonging to each class are dispersed across many of the topics. Often, a complex relationship exists between the topic a document discusses and the class label: positive or negative sentiment is expressed in documents from many different topics, but knowing the topic does not necessarily help in determining the sentiment label. We know from tasks such as Domain Adaptation that sentiment is expressed in different ways under different topics. Topical context can in some cases even reverse the sentiment polarity of words: to be sharp is a good quality for knives but bad for singers. This property can be found in many different document classification tasks. Standard document classification algorithms do not account for or take advantage of topical diversity; instead, classifiers are usually trained with the tacit assumption that topical diversity does not play a role. This thesis is focused on the interplay between the topical structure of corpora, how the target labels in a classification task distribute over the topics and how the topical structure can be utilised in building ensemble models for text classification. We show empirically that a dataset with rich topical structure can be problematic for single classifiers, and we develop two novel ensemble models to address the issues. We focus on two document classification tasks: document level sentiment analysis of product reviews and hierarchical categorisation of news text. For each task we develop a novel ensemble method that utilises topic models to address the shortcomings of traditional text classification algorithms. Our contribution is in showing empirically that the class association of document features is topic dependent. We show that using the topical context of documents for building ensembles is beneficial for some tasks, and present two new ensemble models for document classification. We also provide a fresh viewpoint for reasoning about the relationship of class labels, topical categories and document features.

Li Ngai. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references. / Abstracts in English and Chinese. / Chapter Chapter 1. --- Introduction --- p.1-1 / Chapter 1.1. --- A Brief Review on Pattern Matching --- p.1-1 / Chapter 1.2. --- Objective of the Research Work --- p.1-5 / Chapter 1.3. --- Organization of the Thesis --- p.1-6 / Chapter 1.4. --- Notes on Publications --- p.1-7 / Chapter Chapter 2. --- Background Information --- p.2-1 / Chapter 2.1. --- Introduction --- p.2-1 / Chapter 2.2. --- Review of Block Based Pattern Matching --- p.2-3 / Chapter 2.2.1 --- Gradient Descent Strategy --- p.2-3 / Chapter 2.2.2 --- Simplified Matching Operations --- p.2-10 / Chapter 2.2.3 --- Fast Full-Search Methods --- p.2-14 / Chapter 2.2.4 --- Transform-domain Manipulations --- p.2-19 / Chapter Chapter 3. --- Statistical Rejection Threshold for Pattern Matching --- p.3-1 / Chapter 3.1. --- Introduction --- p.3-1 / Chapter 3.2. --- Walsh Hadamard Transform --- p.3-3 / Chapter 3.3. --- Coarse-to-fine Pattern Matching in Walsh Hadamard Domain --- p.3-4 / Chapter 3.3.1. --- Bounding Euclidean Distance in Walsh Hadamard Domain --- p.3-5 / Chapter 3.3.2. --- Fast Projection Scheme --- p.3-9 / Chapter 3.3.3. --- Using the Projection Scheme for Pattern Matching --- p.3-17 / Chapter 3.4. --- Statistical Rejection Threshold --- p.3-18 / Chapter 3.5. --- Experimental Results --- p.3-22 / Chapter 3.6. --- Conclusions --- p.3-29 / Chapter 3.7. --- Notes on Publication --- p.3-30 / Chapter Chapter 4. --- Fast Walsh Search --- p.4-1 / Chapter 4.1. --- Introduction --- p.4-1 / Chapter 4.2. --- Approximating Sum-of-absolute Difference Using PS AD --- p.4-3 / Chapter 4.3. --- Two-level Threshold Scheme --- p.4-6 / Chapter 4.4. --- Block Matching Using SADDCC --- p.4-10 / Chapter 4.5. --- Optimization of Threshold and Number of Coefficients in PSAD --- p.4-15 / Chapter 4.6. --- Candidate Elimination by the Mean of PSAD --- p.4-23 / Chapter 4.7. --- Computation Requirement --- p.4-28 / Chapter 4.8. --- Experimental Results --- p.4-32 / Chapter 4.9. --- Conclusions --- p.4-45 / Chapter 4.10. --- Notes on Publications --- p.4-46 / Chapter Chapter 5. --- Conclusions & Future Works --- p.5-1 / Chapter 5.1. --- Contributions and Conclusions --- p.5-1 / Chapter 5.1.1. --- Statistical Rejection Threshold for Pattern Matching --- p.5-2 / Chapter 5.1.2. --- Fast Walsh Search --- p.5-3 / Chapter 5.2. --- Future Works --- p.5-4 / References --- p.I

by Liu Zhiyong. / "June 2003." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (p. 125-136). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.