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Global Fuzzy Control Based On Cell Mapping, Tea-Quin Kim May 1996

Global Fuzzy Control Based On Cell Mapping, Tea-Quin Kim

Dissertations

Cell mapping methods can generate global optimal controls for nonlinear dynamic systems. However, the implementation of this approach for on-line control is difficult due to its use of a table-based controller which requires a large amount of memory.

In this dissertation, a cell mapping based systematic method is developed to construct a fuzzy controller to replace the table-based controller for global optimal control of dynamic systems. The method consists of four steps: 1) An optimal control table is generated using a cell mapping algorithm. 2) The cells are linked into trajectories to characterize the optimal dynamic evolution of various cell. …


A Fuzzy Logic Based Approach To Direct Load Control, K. Bhattacharyya, Mariesa Crow May 1996

A Fuzzy Logic Based Approach To Direct Load Control, K. Bhattacharyya, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

Demand side management programs are strategies designed to alter the shape of the load curve. In order to successfully implement such a strategy, customer acceptance of the program is vital. It is thus desirable to design a model for direct load control which may accommodate customer preferences. This paper presents a methodology for optimizing both customer satisfaction and utility unit commitment savings, based on a fuzzy load model for the direct load control of appliances


Adaptive Integration Of Audio And Visual Information Using Discrete And Semi-Continuous Hidden Markov Models In Audiovisual Automatic Speech Recognition, Qin Su Apr 1996

Adaptive Integration Of Audio And Visual Information Using Discrete And Semi-Continuous Hidden Markov Models In Audiovisual Automatic Speech Recognition, Qin Su

Electrical & Computer Engineering Theses & Dissertations

An audiovisual semi-continuous hidden Markov model (HMM)-based Automatic Speech Recognition (ASR) system and an improved method of integrating audio and visual information in an audiovisual discrete HMM-based ASR system are investigated.

In the audiovisual discrete HMM, an adaptive integration formulation is employed, which incorporates the integration into the HMM at a pre-categorical stage. A visual weighting parameter is determined automatically, which allows the relative contribution of audio and visual information to be adjusted adaptively. Using an adaptive weight, the accuracy increased by 13% compared to the same model with no adaptive weight.

The semi-continuous HMM is a class of models …


Speech Feature Computation For Visual Speech Articulation Training, Stefan Auberg Apr 1996

Speech Feature Computation For Visual Speech Articulation Training, Stefan Auberg

Electrical & Computer Engineering Theses & Dissertations

A new version of the Visual Speech Articulation Training Aid was implemented which provides real-time visual feedback for speech articulation training. This version was migrated to a Windows Multimedia PC from a previous version which used a Personal Computer (PC) system and additional specialized and expensive custom hardware. This new version will make the system more available to schools and private users. A new method was developed for computing spectral/temporal features which characterize the speech sounds. In addition to the typical frame-based spectral analysis parameters, the new method represents temporal changes of the spectrum with a small number of features. …


Generalized Hidden Filter Markov Models Applied To Speaker Recognition, John M. Colombi Mar 1996

Generalized Hidden Filter Markov Models Applied To Speaker Recognition, John M. Colombi

Theses and Dissertations

Classification of time series has wide Air Force, DoD and commercial interest, from automatic target recognition systems on munitions to recognition of speakers in diverse environments. The ability to effectively model the temporal information contained in a sequence is of paramount importance. Toward this goal, this research develops theoretical extensions to a class of stochastic models and demonstrates their effectiveness on the problem of text-independent (language constrained) speaker recognition. Specifically within the hidden Markov model architecture, additional constraints are implemented which better incorporate observation correlations and context, where standard approaches fail. Two methods of modeling correlations are developed, and their …


Real Time Control Of Nonlinear Dynamic Systems Using Neuro-Fuzzy Controllers, Amitava Jana Jan 1996

Real Time Control Of Nonlinear Dynamic Systems Using Neuro-Fuzzy Controllers, Amitava Jana

Dissertations

The problem of real time control of a nonlinear dynamic system using intelligent control techniques is considered. The current trend is to incorporate neural networks and fuzzy logic into adaptive control strategies. The focus of this work is to investigate the current neuro-fuzzy approaches from literature and adapt them for a specific application. In order to achieve this objective, an experimental nonlinear dynamic system is considered. The motivation for this comes from the desire to solve practical problems and to create a test-bed which can be used to test various control strategies. The nonlinear dynamic system considered here is an …


Negotiation As A Resource Allocation Process, Fernando Tohme Jan 1996

Negotiation As A Resource Allocation Process, Fernando Tohme

All Computer Science and Engineering Research

The main economic-theoretic approcahes to the problem of resource allocation make little if any reference to negotiation processes. These processes are fundamentally linguistic, based on the exchange of messages among agents. Communication being so fundamental in the characterization of negotiation processes, the analysis of negotiation must emphasize on the structure of the language in which the negotiations take place. Computer science and particularly Artificial Intelligence have provided interesting insights about that linguistic structure. In the first part of this work we present a brief survey of the literature on resource allocation processes in which communication among agents plays a relevant …


The Automated Wingman: An Airborne Companion For Users Of Dis Compatible Flight Simulators, Mark M. Edwards Dec 1995

The Automated Wingman: An Airborne Companion For Users Of Dis Compatible Flight Simulators, Mark M. Edwards

Theses and Dissertations

A major problem encountered by users of distributed virtual environments is the lack of simulators available to populate these environments. This problem is usually remedied by using computer generated entities. Unfortunately, these entities often lack adequate human behavior and are readily identified as non-human. This violates the realism premise of distributed virtual reality and is a major problem, especially in training situations. This thesis addresses the problem by presenting a computer generated entity called the Automated Wingman. The Automated Wingman is a semi-automated computer generated aircraft simulator that operates under the control of a designated lead simulator and integrates distributed …


Text Independent Speaker Verification Using Binary-Pair Partitioned Neural Networks, Claude A. Norton Iii Oct 1995

Text Independent Speaker Verification Using Binary-Pair Partitioned Neural Networks, Claude A. Norton Iii

Electrical & Computer Engineering Theses & Dissertations

A method is presented for the application of binary-pair partitioned neural networks to the task of speaker verification. This technique is based on a previously developed neural network classifier for speaker identification.

The main focus of this research was the development and testing of the algorithms necessary to extend the binary-pair partitioning approach from speaker identification to speaker verification. The method is based on the development of a user profile which is obtained from discriminative data provided by the binary-pair partitioned neural networks.

Experimental results are provided which demonstrate the viability of this approach, using the TIMIT speech corpus for …


A Fuzzy Based Load Model For Power System Direct Load Control, K. Bhattacharyya, Mariesa Crow Sep 1995

A Fuzzy Based Load Model For Power System Direct Load Control, K. Bhattacharyya, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

Demand side management programs are strategies designed to alter the shape of the load curve. In order to successfully implement such a strategy, customer acceptance of the program is vital. It is thus desirable to design a model for direct load control which may accommodate customer preferences. This paper presents a methodology for optimizing both customer satisfaction and utility unit commitment savings, based on a fuzzy load model for the direct load control of appliances.


Full Envelope Control Of Nonlinear Plants With Parameter Uncertainty By Fuzzy Controller Scheduling, Thomas J. Kobylarz Sep 1995

Full Envelope Control Of Nonlinear Plants With Parameter Uncertainty By Fuzzy Controller Scheduling, Thomas J. Kobylarz

Theses and Dissertations

A full envelope controller synthesis technique is developed for multiple-input single-output (MISO) nonlinear systems with structured parameter uncertainty. The technique maximizes the controller's valid region of operation, while guaranteeing pre-specified transient performance. The resulting controller does not require on-line adaptation, estimation, prediction or model identification. Fuzzy Logic (FL) is used to smoothly schedule independently designed point controllers over the operational envelope and parameter space of the system's model. These point controllers are synthesized using techniques chosen by the designer, thus allowing an unprecedented amount of design freedom. By using established control theory for the point controllers, the resulting nonlinear dynamic …


An Adaptive "Natural Law" Fuzzy Controller, Sandeep D. Sequeira May 1995

An Adaptive "Natural Law" Fuzzy Controller, Sandeep D. Sequeira

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fuzzy control has met with a tremendous interest in applications over the past few years. Despite its application potential, a broader industrial exploitation of fuzzy control has been hindered by the lack of standard design methods for fuzzy control systems. Fuzzy controllers have had to be designed on a case-by-case basis employing heuristics and reflecting the designer's limited insight into the control object's behavior. A number of fuzzy theorists have investigated the fuzzy system theoretic problems and results reported in the literature have been encouraging.

This thesis research has explored the notion that fuzzy control, despite being a rule-based control …


Time-Frequency Shift-Tolerance And Counterpropagation Network With Applications To Phoneme Recognition, Li-Minn Ang Jan 1995

Time-Frequency Shift-Tolerance And Counterpropagation Network With Applications To Phoneme Recognition, Li-Minn Ang

Theses : Honours

Human speech signals are inherently multi-component non-stationary signals. Recognition schemes for classification of non-stationary signals generally require some kind of temporal alignment to be performed. Examples of techniques used for temporal alignment include hidden Markov models and dynamic time warping. Attempts to incorporate temporal alignment into artificial neural networks have resulted in the construction of time-delay neural networks. The nonstationary nature of speech requires a signal representation that is dependent on time. Time-frequency signal analysis is an extension of conventional time-domain and frequency-domain analysis methods. Researchers have reported on the effectiveness of time-frequency representations to reveal the time-varying nature of …


An Organizational Learning Approach To Domain Analysis, Scott Henninger, Kris Lappala, Anand Raghavendran Jan 1995

An Organizational Learning Approach To Domain Analysis, Scott Henninger, Kris Lappala, Anand Raghavendran

School of Computing: Conference and Workshop Papers

As the application of computer technology continues to proliferate and diversify, the identification and understanding of application domains is becoming increasingly important to software development methodologies. Domain analysis techniques have been developed to accumulate and formalize the knowledge necessary for successful software reuse. These techniques have been shown to be useful, but suffer from defining the domain too restrictively, burying important relationships deep in domain taxonomies, and prohibiting flexible identification of domains with common issues. Techniques are needed that dynamically detect recurring patterns of activities in development projects. This paper presents a method for developing and refining the knowledge and …


A Cultural Anthropological Overview Of The Niobara/Missouri National Scenic Riverways, Beth R. Ritter, Robert K. Hitchcock, Michelle L. Watson, Michele Voeltz, Thomas D. Thiessen, Oliver Froehling, Rebecca Hautzinger, Judith Campbell Miller, Michele Moray, Leonard R. Bruguier, Gloria Rial Jan 1995

A Cultural Anthropological Overview Of The Niobara/Missouri National Scenic Riverways, Beth R. Ritter, Robert K. Hitchcock, Michelle L. Watson, Michele Voeltz, Thomas D. Thiessen, Oliver Froehling, Rebecca Hautzinger, Judith Campbell Miller, Michele Moray, Leonard R. Bruguier, Gloria Rial

United States Army Corps of Engineers, Omaha District

This document is a cultural anthropological overview and assessment of the Niobrara/Missouri National Scenic Riverways (NIMI). It represents the first formal planning step taken by the National Park service (NPS) to identify the different ethnic and religious groups of people that have historical and/or contemporary ties to the NIMI region. It primarily focuses on American Indian groups that used the NIMI region for various purposes in past historical times. The discussion of American Indian peoples emphasizes the three Federally-recognized tribes that reside in the NIMI region today, the Poncas, Santee Sioux, and Yankton sioux. Other groups that used the NIMI …


Diagnostic And Adaptive Redundant Robotic Planning And Control, Anya Lynn Tascillo Jan 1995

Diagnostic And Adaptive Redundant Robotic Planning And Control, Anya Lynn Tascillo

Graduate Dissertations and Theses

Neural networks and fuzzy logic are combined into a hierarchical structure capable of planning, diagnosis, and control for a redundant, nonlinear robotic system in a real world scenario. Throughout this work levels of this overall approach are demonstrated for a redundant robot and hand combination as it is commanded to approach, grasp, and successfully manipulate objects for a wheelchair-bound user in a crowded, unpredictable environment. Four levels of hierarchy are developed and demonstrated, from the lowest level upward: diagnostic individual motor control, optimal redundant joint allocation for trajectory planning, grasp planning with tip and slip control, and high level task …


On-Line Cursive Korean Character Recognition By Using Curvature Models, Chang-Soo Kim, Byung Hwan Jun, Moo Young Kim, Woo Seong Kim, Jaihie Kim Jan 1995

On-Line Cursive Korean Character Recognition By Using Curvature Models, Chang-Soo Kim, Byung Hwan Jun, Moo Young Kim, Woo Seong Kim, Jaihie Kim

Electrical and Computer Engineering Faculty Research & Creative Works

A cursive Korean character consists of several Korean alphabets where connection is present within and among the alphabets. Recognition of Korean characters can be carried out by splitting each character into smaller primitives. Small line segments can be used as the primitives. But this approach requires too much processing time, for there can be many candidate references to be matched to one input character and each reference usually consists of too many primitives. In this paper, we propose an approach using structural curvature models to overcome the difficulties of using small line segments. These models are obtained by segmenting the …


Will It Fly? A Computer-Based Aircraft Design Tool, Eric G. Woodfin Dec 1994

Will It Fly? A Computer-Based Aircraft Design Tool, Eric G. Woodfin

Honors Capstone Projects and Theses

No abstract provided.


Computer Networks And The Teaching Of English As A Second Language: How Networks Affect Second Language Acquisition, Kirstin J. Reed-Perez Dec 1994

Computer Networks And The Teaching Of English As A Second Language: How Networks Affect Second Language Acquisition, Kirstin J. Reed-Perez

English Theses & Dissertations

No abstract provided.


Objects To The Rescue! Or Httpd: The Next Generation Operating System, Andrew P. Black, Jonathan Walpole Sep 1994

Objects To The Rescue! Or Httpd: The Next Generation Operating System, Andrew P. Black, Jonathan Walpole

Computer Science Faculty Publications and Presentations

This position paper suggests that object-oriented operating systems may provide the means to meet the ever-growing demands of applications. As an example of a successful OOOS, we cite the http daemon. To support the contention that httpd is in fact an operating system, we observe that it implements uniform naming, persistent objects and an invocation meta-protocol, specifies and implements some useful objects, and provides a framework for extensibility.We also believe that the modularity that is characteristic of OO systems should provide a performance benefit rather than a penalty. Our ongoing work in the Synthetix project at OGI is exploring the …


Solvent Substitution Methodology Using Multiattribute Utility Theory And The Analytical Hierarchical Process, Jaimie S. Tiley Sep 1994

Solvent Substitution Methodology Using Multiattribute Utility Theory And The Analytical Hierarchical Process, Jaimie S. Tiley

Theses and Dissertations

This study developed a multicriteria decision making methodology for the ranking of solvent cleaning process alternatives. This includes development of univariate value functions and criteria and the incorporation or required alternative attributes. It also compares the Analytical Hierarchical Process and Multiattribute Utility Theory in reference to a cleaning substitution process. An actual Air Force cleaning process evaluation problem is considered to verify the research. The test problem ranks several cleaning alternatives for the replacement of a hazardous solvent used in the general cleaning of aircraft engine components.


Adaptive Nonlinear Control Using Fuzzy Logic And Neural Networks, Shu-Chieh Chang May 1994

Adaptive Nonlinear Control Using Fuzzy Logic And Neural Networks, Shu-Chieh Chang

Dissertations

The problem of adaptive nonlinear control, i.e. the control of nonlinear dynamic systems with unknown parameters, is considered. Current techniques usually assume that either the control system is linearizable or the type of nonlinearity is known. This results in poor control quality for many practical problems. Moreover, the control system design becomes too complex for a practicing engineer. The objective of this thesis is to provide a practical, systematic approach for solving the problem of identification and control of nonlinear systems with unknown parameters, when the explicit linear parametrization is either unknown or impossible.

Fuzzy logic (FL) and neural networks …


Advanced Navigation For Planetary Vehicles Applying An Approximate Mapping Technique, Timothy R. Mcjunkin May 1994

Advanced Navigation For Planetary Vehicles Applying An Approximate Mapping Technique, Timothy R. Mcjunkin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis provides a method for compressing the information provided by JPL Mars rover obstacle sensors by creating an approximate map of the terrain around the vehicle. This thesis demonstrates that this method provides adequate information for a human operator to negotiate complex obstacles fields.

By dividing the area around the vehicle into regions and classifying each region as to how dangerous (impassable), the sensor data can be accumulated with minimal overhead. The terrain in each region has a number between zero and one, with zero meaning completely passable and one meaning completely impassable. A continuum of possible values between …


Clustering Techniques In Speaker Recognition, Douglas N. Prescott Mar 1994

Clustering Techniques In Speaker Recognition, Douglas N. Prescott

Theses and Dissertations

This thesis presents a comparison based on identification rate, of three clustering techniques applied to cepstral features for speaker identification. LBG vector quantization as developed by Linde, Buzo and Gray; is used to provide benchmark performance for comparison with Fuzzy clustering (based on the unsupervised fuzzy partition-optimal number of classes, UFP-ONC algorithm by Gath and Geva) and an Artificial Neural Network, the Multilayer Perceptron. Cepstral features from the TIMIT, King and AFIT93 corpus speaker databases are used to produce speaker-identification classifiers using each of the clustering algorithms. The experiment reported evaluates the speaker identification performance using the 20-dimensional cepstral features …


Design And Implementation Of Fuzzy Logic Controller For A Process Control Application, Sujit S. Nerurkar Jan 1994

Design And Implementation Of Fuzzy Logic Controller For A Process Control Application, Sujit S. Nerurkar

Theses

Many industrial applications of fuzzy logic control have been reported. This thesis studies and reports the problems associated with the Heat-exchanger temperature control via conventional PID control implemented with Programmable Logic Controllers (PLC) and provides an example of design and implementation of fuzzy logic controllers (FLC's) for a Heat exchanger in a Water for Injection (WFI) system.

After a basic FLC was designed and tested, it is shown how its rule base evolved to achieve superior performance by utilizing additional low-cost sensing information in the process and its environment. A method for the implementation of FLC's into the existing PLC …


Fuzzy Knowledge-Based Approach To Treating Uncertainty In Inventory Control, Dobrilla Petrovic, Edward Sweeney Jan 1994

Fuzzy Knowledge-Based Approach To Treating Uncertainty In Inventory Control, Dobrilla Petrovic, Edward Sweeney

Articles

Inventory control in complex manufacturing environments encounters various sources of uncertainity and imprecision. This paper presents one fuzzy knowledge-based approach to solving the problem of order quantity determination, in the presence of uncertain demand, lead time and actual inventory level. Uncertain data are represented by fuzzy numbers, and vaguely defined relations between them are modeled by fuzzy if-then rules. The proposed representation and inference mechanism are verified using a large numbers of examples. The results of three representative cases are summarized. Finally a comparison between the developed fuzzy knowledge-based and traditional, probabilistic approaches is discussed.


Journal Of Engineering Education Round Table: Reflections On The Grinter Report, James G. Harris, Eugene M. Deloatch, William R. Grogan, Irene C. Peden, John R. Whinnery Jan 1994

Journal Of Engineering Education Round Table: Reflections On The Grinter Report, James G. Harris, Eugene M. Deloatch, William R. Grogan, Irene C. Peden, John R. Whinnery

Electrical Engineering

The Round Table is a new presentation format for the Journal of Engineering Education. The purpose of the Round Table is to present the comments of several distinguished individuals about a topic as well as their responses to the comments offered by their colleagues. For the initial Journal of Engineering Education Round Table we asked for reflections about the Grinter Report, published in September 1955.

After a brief introduction to the topic of discussion, the invited participants present their views, and, then, respond to the remarks of their colleagues. The goal is two-fold: to present a spectrum of views on …


Investigation Into Model-Based Fuzzy Logic Control, Michael W. Logan Dec 1993

Investigation Into Model-Based Fuzzy Logic Control, Michael W. Logan

Theses and Dissertations

This thesis investigates the feasibility of a proposed hybrid linear/Fuzzy controller for nonlinear plants. The proposed controller concept is based on the use of multiple linearizations of a nonlinear plant, which describe the dynamics of perturbations about equilibrium points throughout the desired envelope of operation. A bank of linear compensators is developed, each corresponding to a linearized plant about a different equilibrium. The multiple control signals generated by the bank of compensators are then weighted and summed using Fuzzy Logic to produce a composite control perturbation signal, which is used to drive the nonlinear plant. Experiments were conducted to test …


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 9, Number 9, November 1993, College Of Engineering And Computer Science, Wright State University Nov 1993

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 9, Number 9, November 1993, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A fourteen page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.


Declarative Representations Of Multiagent Systems, Munindar P. Singh, Michael N. Huhns, Larry M. Stevens Oct 1993

Declarative Representations Of Multiagent Systems, Munindar P. Singh, Michael N. Huhns, Larry M. Stevens

Faculty Publications

This paper explores the specification and semantics of multiagent problem-solving systems, focusing on the representations that agents have of each other. It provides a declarative representation for such systems. Several procedural solutions to a well-known test-bed problem are considered, and the requirements they impose on different agents are identified. A study of these requirements yields a representational scheme based on temporal logic for specifying the acting, perceiving, communicating, and reasoning abilities of computational agents. A formal semantics is provided for this scheme. The resulting representation is highly declarative, and useful for describing systems of agents solving problems reactively.