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Fate And Transport Of Tce-Petroleum Hydrocarbon Mixture At Uttr, G. Nash Quashiga, Richard C. Peralta Jan 1992

Fate And Transport Of Tce-Petroleum Hydrocarbon Mixture At Uttr, G. Nash Quashiga, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

In 1988 a preliminary assessment (PA) study was conducted at Chemical Disposal Pit No. 4 to address several concerns of Hill Air Force Base (HAFB), the facility operators. The objectives of the PA were; i) to assess the potential for organic chemical releases to the subsurface environment, and ii) to determine the need for any immediate control measures, if the subsurface environment were threatened.


Optimizing Perennial Groundwater Yield Planning For Nonlinear Systems: Approach Comparison, Shu Takahashi, Richard C. Peralta Jan 1992

Optimizing Perennial Groundwater Yield Planning For Nonlinear Systems: Approach Comparison, Shu Takahashi, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Four alternative simulation/optimization models useful for computing optimal sustained-yield (steady-state) groundwater pumping strategies are compared in terms of formulation, solution procedure, accuracy, and computational efficiency. The different models require different computer processing time and memory. For the aquifer tested system, if more than 10% of the cells have pumping as a decision variable, a fully linearized embedding model will require less computer memory than any other model. All the models address linear and nonlinear steady-state flow in multilayer, unconfined/confined aquifers. They also address several types of nonsmooth external flows. Newly presented are a response matrix model solving external flows described …


Optimizing Ground Water Planning And Management, Richard C. Peralta, L. S. Willardson Jan 1992

Optimizing Ground Water Planning And Management, Richard C. Peralta, L. S. Willardson

Civil and Environmental Engineering Faculty Publications

Simulation/optimization (S/0) models can be used to speed the process of computing long term groundwater pumping strategies. These combined models can also greatly ease the planning tasks of water management agencies. They make the process of computing optimal perennial yield groundwater management strategies fairly straightforward. S/0 models dramatically improve conjunctive water management and can help minimize the cost of groundwater contaminant clean-up. The differences between S/0 models and the simulation (S) models currently used by over 98 % of practitioners are illustrated with recent applications of S/0 models in regional planning.


Best Management Practices (Bmps) To Minimize Nitrate Leaching From Irrigated Potatoes, Ahmad Yar Ranjha, Richard C. Peralta, Robert W. Hill Jan 1992

Best Management Practices (Bmps) To Minimize Nitrate Leaching From Irrigated Potatoes, Ahmad Yar Ranjha, Richard C. Peralta, Robert W. Hill

Civil and Environmental Engineering Faculty Publications

Numerous preliminary simulations are again performed to determine the smallest fertilizer amount, applied througii sprinkler irrigations (chemigation), that should still yield 15.3 tons of potatoes per acre. Applying only 68 lbs/ac of ammonium nitrate fertilizer in the first irrigation on June 28, should be sufficient. Again, total crop N uptake equals potential crop N uptake throughout the growing season. Except for the net income and applied fertilizer N uptake efficiency, all the other results computed by NLEAP (Figure 4 and Table 1) are very similar to results of scenario II. Applied fertilizer N uptake efficiency is the highest (91%) in …


Optimal Groundwater Quantity/Quality Planning For Salt Lake Valley, Ali Gharbi, Richard C. Peralta Jan 1992

Optimal Groundwater Quantity/Quality Planning For Salt Lake Valley, Ali Gharbi, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Generally, the embedding technique for optimizing groundwater management has been limited to small scale or steady-state groundwater flow management cases. The embedding approach causes sparse, highly structured constraint matrices which have been sometimes difficult to solve. Embedding applications have been limited by lack of: optimization algorithms able to easily address such matrices for large scale problems, and efficient methods for addressing common nonlinearities and converging to a solution. Computer software, USUEM, addresses these issues by: creation of alternative linear, nonlinear, combined and partitioned formulations of the same problem, implemention of an efficient cycling procedure, and good selection of optimization algorithm …


Pluman, Decision Support System For Groundwater Contaminant Plume Simulation/Optimization Management Model, Herminio H. Suguino, Richard C. Peralta Jan 1992

Pluman, Decision Support System For Groundwater Contaminant Plume Simulation/Optimization Management Model, Herminio H. Suguino, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

No abstract provided.


Optimal Management Of Irrigation And Vadose Zone Pesticide Transport, M. A. Hegazy, Richard C. Peralta Jan 1992

Optimal Management Of Irrigation And Vadose Zone Pesticide Transport, M. A. Hegazy, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

A management model is developed for maximizing crop yield while avoiding unacceptable pesticide leaching. Utilized constraint equations: maintain a soil moisture volume balance, describe downward pesticide transport, and limit the amount of pesticide reaching groundwater. The reported optimization model is the first which includes unsaturated zone pesticide transport. It is designed to help prevent nonpoint-source contamination of shallow groundwater aquifers. The model computes optimal irrigation amounts for given soil, crop, chemical, and climate data and irrigation frequencies. The model is tested for different irrigation scenarios. The modeling approach is promising as a tool to aid developing environmentally sound agricultural production …


Optimal Perennial Groundwater Yield Planning For The East Shore Area, Utah, Shu Takahashi, Richard C. Peralta Jan 1992

Optimal Perennial Groundwater Yield Planning For The East Shore Area, Utah, Shu Takahashi, Richard C. Peralta

Civil and Environmental Engineering Faculty Publications

Computer models are developed for computing optimal perennial groundwater withdrawal strategies for the East Shore Area of Utah's Great Salt Lake. The underlying aquifer has three confined or unconfined layers. Both embedding and response matrix (RM) approaches are tested and compared. Historically, it has been difficult to incorporate simulation of an unconfined aquifer and many external flow equations described by nonsmooth functions within linear programming models. RM models normally assume system linearity. The presented RM model overcomes this difficulty using cycling and influence coefficients generated with a modified MODFLOW model. In this groundwater flow simulation model, the above nonlinear terms …


Influence Of Heavy Metal Concentration On Rotating Biological Contrator Performance, Huei-Sheng Cheng Dec 1991

Influence Of Heavy Metal Concentration On Rotating Biological Contrator Performance, Huei-Sheng Cheng

Theses

Seven heavy metals ( Fe+2, Mn+2, Zn+2, Ag+, Pb+2, Cu+2, Cd+2 ) at various concentrations were investigated in a Rotating Biological Contactor (RBC) system. The experimental data indicated that the degree of heavy metal toxicity in the biological system mainly depended on the ratio of inflow heavy metal concentration to organic loading. The optimal ratio of heavy metal to organic loading was determined on the basis of the maximum removal of chemical oxygen demand (COD) under different operating conditions. In addition, the effect of heavy metal on …


Three Dimensional Visualisation Of Tmj Anatomy Using Mri Techniques, Mythreyi T. Krishnaswamy Dec 1991

Three Dimensional Visualisation Of Tmj Anatomy Using Mri Techniques, Mythreyi T. Krishnaswamy

Theses

The best assessment of temporomandibular joint (TMJ) can only be done by the scanning the jaw and getting an image without invivo analysis which causes patient discomfort. There have been innumerable efforts to get the best view using CT techniques for three dimensional visualisation. But very few have done work using MRI techniques.

The TMJ is an integral part of the jaw and helps in mastication and biting. Since the joint is a hinge sliding articulation any dislocation causes immense pain and discomfort.

To get a better assessment of the TMJ, MRI techniques have been used for data acquisition. The …


Temperature Regulation Post Hemorrhagic Shock In Rats : Atheoretical Analysis, Kahambwe Shungu Dec 1991

Temperature Regulation Post Hemorrhagic Shock In Rats : Atheoretical Analysis, Kahambwe Shungu

Theses

The adequacy of a mathematical model in simulating temperature regulation in rats after resuscitation from hemorrhagic shock is investigated. This model, proposed elsewhere, was devised to study temperature profiles during hyperthermia in humans.

Hemorrhagic shock was achieved by bleeding rats to an average mean arterial pressure (MAP) of 30mmHg. The rats were then maintained at this MAP for up to four hours by withdrawing or reinfusing the shed blood. One group (the control group), was allowed to return to normal body temperature after the shock episode without external intervention. A second group (microwave group) was irradiated, for an average of …


Image Deblurring For Visualization Of Coronary Microcirculation, Kaijun Wang Dec 1991

Image Deblurring For Visualization Of Coronary Microcirculation, Kaijun Wang

Theses

Blurred images of the rat coronary microcirculation have been obtained and processed. Heart motion, blood flow and noise cause the blur of the images. The objective of this thesis work was to study the effects of these factors on image quality and assess several models for image deblurring. The Wiener Filter and the Powei Spectrum Equalization Filter were implemented and were added to the existing image processing software. The images obtained after the application of these filters showed significant improvement over the original blurred images.


Biodegradation Of Tnt (2,4,6-Trinitrotoluene), Jin Lou Dec 1991

Biodegradation Of Tnt (2,4,6-Trinitrotoluene), Jin Lou

Theses

This study summaries the results of various methods treating 2,4,6-trinitrotoluene (TNT). Review of available literatures revealed that the most commonly used techniques in full-scale plant for TNT removal are chemical oxidation and carbon adsorption.

From economic point of view, the biological treatment system will be much more cost-effective. Various methods for improving the efficiency of biological system treating TNT wastewater were developed in the laboratory. Current laboratory results show that by isolating appropriate microorganisms under adequate conditions, TNT wastes can be degraded successfully.

At the some time, some pretreatment technologies are recommended in this study for improving the performance of …


Development Of An Expert System For The Safety Of Workers From Electrical Hazards At Work Place, Faizul Islam Dec 1991

Development Of An Expert System For The Safety Of Workers From Electrical Hazards At Work Place, Faizul Islam

Theses

This thesis presents the development of an expert system for the safety of workers from electrical hazards at work place.

The objective of this work is to show how an expert system within the workplace can be used in helping to create an effective safety program.

An effective expert system for electrical safety have been developed for the workers to prevent accidents from electrical hazards using the safety regulations of Occupational Safety and Health Administration.

The regulations developed by OSHA have been incorporated in rule based expert system which can be accessed by any non computer professional and the system …


Software Development For Analysis Of Stochastic Petri Nets Using Transfer Functions, Aman U. Jamwal Dec 1991

Software Development For Analysis Of Stochastic Petri Nets Using Transfer Functions, Aman U. Jamwal

Theses

This thesis research is an implementation of a closed-form analytical technique for study, evaluation and analysis of Stochastic Petri Nets (SPN). The technique is based on a theorem that an isomorphism exists between an SPN and a Markov Chain. The procedure comprises five main steps: reachability graph generation of the underlying Petri net, transformation of the reachability graph to a state machine Petri net, calculation of transfer functions, computation of equivalent transfer functions via Mason's rule, and computation of performance parameters of the SPN model from the equivalent transfer functions and their derivatives. The software is developed in UNIX using …


Radar System Classification Using Neural Networks, David M. Cameron Dec 1991

Radar System Classification Using Neural Networks, David M. Cameron

Theses and Dissertations

This study investigated methods of improving the accuracy of neural networks in the classification of large numbers of classes. A literature search revealed that neural networks have been successful in the radar classification problem, and that many complex problems have been solved using systems of multiple neural networks. The experiments conducted were based on 32 classes of radar system data. The neural networks were modelled using a program called the Neural Graphics Analysis System. It was found that the accuracy of the individual neural networks could be increased by controlling the number of hidden nodes, the relative numbers of training …


Binaural Sound Localization Using Neural Networks, Rushby C. Craig Dec 1991

Binaural Sound Localization Using Neural Networks, Rushby C. Craig

Theses and Dissertations

The purpose of this study was to investigate the use of Artificial Neural Networks to localize sound sources from simulated, human binaural signals. Only sound sources originating from a circle on the horizontal plane were considered. Experiments were performed to examine the ability of the networks to localize using three-different feature sets. The feature sets used were: time-samples of the signals, mena Fast Fourier Transform magnitude and cross correlation data, and auto-correlation and cross correlation data. The two different types of sound source signals considered were tones and gaussian noise. The feature set which yielded the best results in terms …


Analysis Of Visual Illusions Using Multiresolution Wavelet Decomposition Based Models, John S. Laing Dec 1991

Analysis Of Visual Illusions Using Multiresolution Wavelet Decomposition Based Models, John S. Laing

Theses and Dissertations

This thesis provides alternatives to the explanation that spatial filtering is responsible for the perception of illusory contours in the Kanisza Triangle illusion. Specifically, we use a Multiresolution Wavelet Decomposition to divide an image into spatial-frequency bands that are used as inputs to three biologically motivated models. The thesis includes a brief tutorial of Wavelet theory and an in-depth explanation of our implementation of recently published algorithms for Multiresolution Wavelet Analysis. The first model is based on the saccadic movements of the human eye. It demonstrates the importance of the high spatial-frequency content of an image in the formulation of …


Face Recognition With The Karhunen-Loeve Transform, Pedro F. Suarez Dec 1991

Face Recognition With The Karhunen-Loeve Transform, Pedro F. Suarez

Theses and Dissertations

The major goal of this research was to investigate machine recognition of faces. The approach taken to achieve this goal was to investigate the use of Karhunen-Loe've Transform (KLT) by implementing flexible and practical code. The KLT utilizes the eigenvectors of the covariance matrix as a basis set. Faces were projected onto the eigenvectors, called eigenfaces, and the resulting projection coefficients were used as features. Face recognition accuracies for the KLT coefficients were superior to Fourier based techniques. Additionally, this thesis demonstrated the image compression and reconstruction capabilities of the KLT. This theses also developed the use of the KLT …


Image Segmentation Using Affine Wavelets, Steven E. Smiley Dec 1991

Image Segmentation Using Affine Wavelets, Steven E. Smiley

Theses and Dissertations

This thesis discusses the use of the multiresolution representation and Radial Basis Function (RBF) neural networks to segment both FLIR and SAR imagery. The multiresolution approximation coefficients are used as features into the RBF network which learns to distinguish between different cultural and natural regions or objects. The wavelets used are Mallat's spline wavelet and Daubechies' compactly supported wavelets. Additionally, this thesis provides an explanation of wavelets in a tutorial manner. It introduces wavelet theory and discusses two different approaches to generating the multiresolution or wavelet representation.


Principal Base Parameter Analysis: Implementation And Analysis In An Adaptive Model-Based Robotic Controller, Gregory L. Showman Dec 1991

Principal Base Parameter Analysis: Implementation And Analysis In An Adaptive Model-Based Robotic Controller, Gregory L. Showman

Theses and Dissertations

Principal Base Parameter Analysis (PBPA) is a general and systematic procedure for determining the dynamic parameters that directly contribute to the joint torques of a manipulator, ranked in order of sensitivity. The feasibility of employing PBPA as an aid in the design and tuning of adaptive model-based controllers for industrial manipulators is rigorously investigated. This is accomplished by employing PBPA to determine the minimal size of the adaptive parameter vector and more importantly, to develop a less heuristic procedure for controller tuning. A simple, step-by-step procedure is developed wherein the manipulator torque equations are used in conjunction with PBPA to …


Function Prediction Using Recurrent Neural Networks, Randall L. Lindsey Dec 1991

Function Prediction Using Recurrent Neural Networks, Randall L. Lindsey

Theses and Dissertations

A fully recurrent neural network was applied to the function prediction problem. The real-time recurrent learning (RTRL) algorithm was modified and tested for use as a viable function predictor. The modification gave the algorithm a variable learning rate and a linear/sigmoidal output selection. Verifying the networks ability to temporally learn both the classic exclusive-OR (XOR) problem and the internal state problem, the network was then used to simulate the frequency response of a second order IIR lowpass Butterworth filter. The recurrent network was then applied to two problems: head position tracking, and voice date reconstruction. The accuracy at which the …


Wave Propagation In A Randomly Inhomogeneous Medium - A Study Of The Problem, Kyle Hunter Dec 1991

Wave Propagation In A Randomly Inhomogeneous Medium - A Study Of The Problem, Kyle Hunter

Theses and Dissertations

The problem of calculating the scintillation index of an atmospherically propagating spherical wave is examined. The fourth statistical moment of the complex field is obtained by using Feynman (path) integral techniques applied to the stochastic parabolic equation. The general trajectory of each Feynman integral is approximated by a truncated Fourier-sine series and the infinite-fold integration of the Feynman integral is reduced to a three-fold Riemann integral which is shown to match results derived under different assumptions. This thesis is highly tutorial.


Image Analysis Using Gabor Transforms: Correlated With Human Saccadic Movement Data To Identify The Human Visual Search Strategy, Ralph J. St John Dec 1991

Image Analysis Using Gabor Transforms: Correlated With Human Saccadic Movement Data To Identify The Human Visual Search Strategy, Ralph J. St John

Theses and Dissertations

This thesis investigated whether a relationship exists between the Gabor Correlation Coefficient (GCC) magnitudes of fixation points for a set of images viewed by six subjects and the human visual search strategy. A couple of different relationships were investigated. First, the data were analyzed to determine if the GCC magnitudes of human fixation points predicted the time ordered sequence of human fixation points during the performance of a visual search. Second, the data were analyzed to determine if there was a significant difference between the GCC magnitudes of the human fixation points and the GCC magnitudes of a random set …


Application Of Finite Element Modeling And Analysis To The Design Of Positive Pressure Oxygen Masks, Bruce H. Bitterman Dec 1991

Application Of Finite Element Modeling And Analysis To The Design Of Positive Pressure Oxygen Masks, Bruce H. Bitterman

Theses and Dissertations

This study investigated tools and techniques for performing finite element analysis of the MBU-20/P pilot's oxygen mask. The problem which was investigated was the fit of the mask to the face at Positive Pressure Breathing (PPB) pressures. Deformed geometry of the mask and reaction forces on the face were calculated to provide a measure of the fit. The MBU-20/P mask was first digitized by 3-D digitizer. A computer program was written to translate the digitized coordinate data to a finite element format for two commercial packages. The packages targeted were SDRC I-DEAS and PDA PATRAN. Other supplementary programs were written …


Gabor Segmentation Of High Resolution Synthetic Aperture Radar Imagery, Michael A. Hazlett Dec 1991

Gabor Segmentation Of High Resolution Synthetic Aperture Radar Imagery, Michael A. Hazlett

Theses and Dissertations

This thesis investigates the use of Gabor filters and a radial basis function (RBF) network for segmentation of high resolution (1 foot by 1 foot) synthetic aperture radar (SAR) imagery. Processing involved correlation between the SAR imagery and Gabor functions. Two methods for selecting the optimal Gabor filters are presented. This research used complex Gabor functions and operated on single polarization HH complex data. Following the selection f the proper Gabor filters, correlation coefficients for each image were calculated and used as features for the RBF network. Provided are results demonstrating how Gabor processing and a RBF network provide image …


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 7, Number 8, November 1991, College Of Engineering And Computer Science, Wright State University Nov 1991

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 7, Number 8, November 1991, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

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


Integrated Anaerobic-Aerobic System For The Biodegradation Of Highly Chlorinated Aromatic Compounds, Cheng-Ming Kung Oct 1991

Integrated Anaerobic-Aerobic System For The Biodegradation Of Highly Chlorinated Aromatic Compounds, Cheng-Ming Kung

Dissertations

A two-step process was developed for the complete mineralization of hazardous chlorinated aromatic compounds. The system consisted of an anaerobic reactor, in which reductive dehalogenation took place, coupled with an aerobic reactor in which the complete mineralization of the products of the anaerobic dehalogenation occurred.

A mixed anaerobic culture from a municipal sewage treatment plant was enriched and then immobilized on silica-based porous beads to treat 2,4,6-trichlorophenol (TCP), which is the model target compound in this work. In the anaerobic reactor, TCP was degraded to 2,4-dichlorophenol which was, in turn, reduced to 4-chlorophenol (4-CP). Stoichiometric amounts of 4-CP were recovered …


Disc Size Scale-Up In Rotating Biological Contactor System, Chi-Sheng Chang Oct 1991

Disc Size Scale-Up In Rotating Biological Contactor System, Chi-Sheng Chang

Theses

Disc size scale-up of prototype and small-scale RBC plants are successfully developed by applying the 114 data sets obtained from 12 RBC plants to the evaluation of percent sBOD remaining. These data analyses are performed by the least square method, therefore, the scale-up factors of the prototype and the small-scale are determined at different hydraulic loading. Furthermore, the relationship between scale-up factor and the disc diameter are established under the given flow rate, the number of stages, and the number of discs. A group of Curves are obtained and can be utilized for the full-scale RBC plant preliminary design. The …


Calcium Channel Dynamics In Hippocampal Neurons : Simulation And Physiological Studies, Prasad D. Jasthi Oct 1991

Calcium Channel Dynamics In Hippocampal Neurons : Simulation And Physiological Studies, Prasad D. Jasthi

Theses

Mathematical modelling and computer simulations of neurons was presented by various researchers in the past. Computer simulations provide a time efficient and cost effective method to obtain required information about the physiological system. The objective of this project is to study the kinetics of calcium channels in hippocampal neurons. In an attempt to study the calcium channel activity we have developed a mathematical model for the CA3 region of the hippocampus and have analysed the calcium current noise obtained from the physiological recordings. The Simulation results had reproduced the action potential and activities of sodium and potassium channels, but did …