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Content-based image retrieval using relevance feedback
Title
Content-based image retrieval using relevance feedback.
Creator
Marques, Oge, Florida Atlantic University, Furht, Borko, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description
This dissertation presents the results of research that led to the development of a complete, fully functional, image search and retrieval system with relevance feedback capabilities, called MUSE (MUltimedia SEarch and Retrieval Using Relevance Feedback). Two different models for searching for a target image using relevance feedback have been proposed, implemented, and tested. The first model uses a color-based feature vector and employs a Bayesian learning algorithm that updates the...
Show moreThis dissertation presents the results of research that led to the development of a complete, fully functional, image search and retrieval system with relevance feedback capabilities, called MUSE (MUltimedia SEarch and Retrieval Using Relevance Feedback). Two different models for searching for a target image using relevance feedback have been proposed, implemented, and tested. The first model uses a color-based feature vector and employs a Bayesian learning algorithm that updates the probability of each image in the database being the target based on the user's actions. The second model uses cluster analysis techniques, a combination of color-, texture-, and edge(shape)-based features, and a novel approach to learning the user's goals and the relevance of each feature for a particular search. Both models follow a purely content-based image retrieval paradigm. The search process is based exclusively on image contents automatically extracted during the (off-line) feature extraction stage. Moreover, they minimize the number and complexity of required user's actions, in contrast with the complexity of the underlying search and retrieval engine. Results of experiments show that both models exhibit good performance for moderate-size, unconstrained databases and that a combination of the two outperforms any of them individually, which is encouraging. In the process of developing this dissertation, we also implemented and tested several image features and similarity measurement combinations. The result of these tests---performed under the query-by-example (QBE) paradigm---served as a reference in the choice of which features to use in the relevance feedback mode and confirmed the difficulty in encoding the understanding of image similarity into a combination of features and distances without human assistance. Most of the code written during the development of this dissertation has been encapsulated into a multifunctional prototype that combines image searching (with or without an example), browsing, and viewing capabilities and serves as a framework for future research in the subject.
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Date Issued
2001
PURL
http://purl.flvc.org/fcla/dt/11954
Subject Headings
Information storage and retrieval systems, Image processing--Digital techniques, Feedback control systems
Format
Document (PDF)
Spectral refinement to speech enhancement
Title
Spectral refinement to speech enhancement.
Creator
Charoenruengkit, Werayuth., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description
The goal of a speech enhancement algorithm is to remove noise and recover the original signal with as little distortion and residual noise as possible. Most successful real-time algorithms thereof have done in the frequency domain where the frequency amplitude of clean speech is estimated per short-time frame of the noisy signal. The state of-the-art short-time spectral amplitude estimator algorithms estimate the clean spectral amplitude in terms of the power spectral density (PSD) function...
Show moreThe goal of a speech enhancement algorithm is to remove noise and recover the original signal with as little distortion and residual noise as possible. Most successful real-time algorithms thereof have done in the frequency domain where the frequency amplitude of clean speech is estimated per short-time frame of the noisy signal. The state of-the-art short-time spectral amplitude estimator algorithms estimate the clean spectral amplitude in terms of the power spectral density (PSD) function of the noisy signal. The PSD has to be computed from a large ensemble of signal realizations. However, in practice, it may only be estimated from a finite-length sample of a single realization of the signal. Estimation errors introduced by these limitations deviate the solution from the optimal. Various spectral estimation techniques, many with added spectral smoothing, have been investigated for decades to reduce the estimation errors. These algorithms do not address significantly issue on quality of speech as perceived by a human. This dissertation presents analysis and techniques that offer spectral refinements toward speech enhancement. We present an analytical framework of the effect of spectral estimate variance on the performance of speech enhancement. We use the variance quality factor (VQF) as a quantitative measure of estimated spectra. We show that reducing the spectral estimator VQF reduces significantly the VQF of the enhanced speech. The Autoregressive Multitaper (ARMT) spectral estimate is proposed as a low VQF spectral estimator for use in speech enhancement algorithms. An innovative method of incorporating a speech production model using multiband excitation is also presented as a technique to emphasize the harmonic components of the glottal speech input., The preconditioning of the noisy estimates by exploiting other avenues of information, such as pitch estimation and the speech production model, effectively increases the localized narrow-band signal-to noise ratio (SNR) of the noisy signal, which is subsequently denoised by the amplitude gain. Combined with voicing structure enhancement, the ARMT spectral estimate delivers enhanced speech with sound clarity desirable to human listeners. The resulting improvements in enhanced speech are observed to be significant with both Objective and Subjective measurement.
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Date Issued
2009
PURL
http://purl.flvc.org/FAU/186327
Subject Headings
Adaptive signal processing, Digital techniques, Spectral theory (Mathematics), Noise control, Fuzzy algorithms, Speech processing systems, Digital techniques
Format
Document (PDF)
Applications of pulse width modulation to LEDs, fuel cells and battery technology
Title
Applications of pulse width modulation to LEDs, fuel cells and battery technology.
Creator
Watt, Wayne W., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description
It has become a case of great desire and, in some instances, a requirement to have systems in engineering be energy efficient, in addition to being effectively powerful. It is rare that there is a single technique that has the range to make this possible in a wide collection of areas in the field. The work done in this thesis exhibits how Pulse Width Modulation (PWM) bridges LEDs, plug in vehicles, fuel cells and batteries, all seemingly different sub categories of electrical engineering. It...
Show moreIt has become a case of great desire and, in some instances, a requirement to have systems in engineering be energy efficient, in addition to being effectively powerful. It is rare that there is a single technique that has the range to make this possible in a wide collection of areas in the field. The work done in this thesis exhibits how Pulse Width Modulation (PWM) bridges LEDs, plug in vehicles, fuel cells and batteries, all seemingly different sub categories of electrical engineering. It stems from an undergraduate directed independent study supervised by Dr. Zilouchian that encircled LEDs and electric vehicles and how they contribute to a smart electric grid. This thesis covers the design and development of a prototype board that test how PWM saves energy, prolongs lifespan and provides a host of customizable features in manufactured LED lights that are used in the marine industry. Additionally, the concept of charging batteries that provide power to electric vehicles was explored. It is stressed that consumers who are interested in electric vehicles are concerned about refueling and recharge times. It is natural that a competing product, such as the electric vehicle in a world dominated by internal combustion engines, will perform on par if not better than existing choices. Tests are conducted to investigate the methods of fast battery charging and the challenges this technique creates. Attention is also given to the development of a pulsed Proton Exchange Membrane (PEM) fuel cell, specifically to prove whether pulse modulation is more efficient in a hydrogen producing fuel cell as opposed to direct-driven voltage and current alternatives.
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Date Issued
2011
PURL
http://purl.flvc.org/FAU/3174313
Subject Headings
Power electronics, Digital control systems, Electric current converters, Fuel cells, Economic aspects
Format
Document (PDF)
Interactive computer aided digital control design
Title
Interactive computer aided digital control design.
Creator
Yakali, Huseyin Hakan., Florida Atlantic University, Roth, Zvi S., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description
This thesis outlines the design philosophy and implementation aspects of a new interactive CAD tool implemented in BASIC language on an IBM PC/AT computer for single input single output (SISO) digital control systems. The direct Digital Control design method presented is classical in nature. The program main features are: (1) The use of Modified z-transform to model the effects of transport delay due to control computation time. (2) The use of windows on a split screen to allow the designer...
Show moreThis thesis outlines the design philosophy and implementation aspects of a new interactive CAD tool implemented in BASIC language on an IBM PC/AT computer for single input single output (SISO) digital control systems. The direct Digital Control design method presented is classical in nature. The program main features are: (1) The use of Modified z-transform to model the effects of transport delay due to control computation time. (2) The use of windows on a split screen to allow the designer observation of the closed-loop step response while systematically shaping a root locus or synthesizing closed-loop pole/zero patterns. (3) Display of system response in between sampling instants.
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Date Issued
1988
PURL
http://purl.flvc.org/fcla/dt/14488
Subject Headings
Computer-aided design, Digital control systems, Engineering design--Data processing
Format
Document (PDF)
Configuration and assessment of hardware-in-the-loop-simulation with high resolution data to coordinate traffic signals
Title
Configuration and assessment of hardware-in-the-loop-simulation with high resolution data to coordinate traffic signals.
Creator
Klanac, Ivica, Stevanovic, Aleksandar, Florida Atlantic University, College of Engineering and Computer Science, Department of Civil, Environmental and Geomatics Engineering
Abstract/Description
Today, the information (signal timings, detector extension, phase sequence, etc.) to install traffic lights on the street are obtained from traffic software simulations platforms, meaning that information from simulation is not tested on the field (intersection where it will be installed) before the installation. Many installed controllers on the street use time of day (TOD) patterns due to cheaper cost than adaptive traffic control systems, but that is not the best solution for traffic...
Show moreToday, the information (signal timings, detector extension, phase sequence, etc.) to install traffic lights on the street are obtained from traffic software simulations platforms, meaning that information from simulation is not tested on the field (intersection where it will be installed) before the installation. Many installed controllers on the street use time of day (TOD) patterns due to cheaper cost than adaptive traffic control systems, but that is not the best solution for traffic volume changes that can occur during the day or even a month. To improve traffic signal operation most of the traffic signal controllers in the same corridor or zone operate in coordination mode. Furthermore, phases need to be in coordination to achieve “green wave”. Green wave is term used when in corridor traffic lights allow continues flow of traffic through intersections that are coordinated.
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Date Issued
2016
PURL
http://purl.flvc.org/fau/fd/FA00004709, http://purl.flvc.org/fau/fd/FA00004709
Subject Headings
Digital control systems, Digital integrated circuits -- Design and construction, Hardware in the loop simulation, Highway engineering -- Safety measures, Traffic engineering -- Technological innovations, Traffic flow -- Management, Traffic signs and signals -- Control systems -- Methodology
Format
Document (PDF)
method for adding multimedia knowledge for improving intrusion detection systems
Title
A method for adding multimedia knowledge for improving intrusion detection systems.
Creator
Baillargeon, Pierre Elliott., Florida Atlantic University, Marques, Oge
Abstract/Description
Intrusion Detection Systems (IDS) are security tools which monitor systems and networks for malicious activity. In saturated network links the amount of data present for analysis can overwhelm them, resulting in potentially undetected attacks. Many of these network links contain significant amounts of multimedia traffic which may seem to contribute to the problem, however our work suggests otherwise. This thesis proposes a novel method to classify and analyze multimedia traffic in an effort...
Show moreIntrusion Detection Systems (IDS) are security tools which monitor systems and networks for malicious activity. In saturated network links the amount of data present for analysis can overwhelm them, resulting in potentially undetected attacks. Many of these network links contain significant amounts of multimedia traffic which may seem to contribute to the problem, however our work suggests otherwise. This thesis proposes a novel method to classify and analyze multimedia traffic in an effort to maximize the efficiency of IDS. By embedding multimedia-specific knowledge into IDS, trusted multimedia contents can be identified and allowed to bypass the detection engine, thereby allowing IDS to focus its limited resources on other traffic. The proposed framework also enables IDS to detect multimedia-specific exploits which would otherwise pass under the radar. Results of our experiments confirm our claims and show substantial CPU savings in both streaming and non-streaming scenarios.
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Date Issued
2005
PURL
http://purl.flvc.org/fcla/dt/13242
Subject Headings
Computer networks--Security measures, Computers--Access control, Electronic countermeasures, Digital watermarking, Multimedia systems--Security measures
Format
Document (PDF)