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Efficient Mapping Of Neural Network Models On A Class Of Parallel Architectures., Behnam Seyed Arad
Efficient Mapping Of Neural Network Models On A Class Of Parallel Architectures., Behnam Seyed Arad
LSU Historical Dissertations and Theses
This dissertation develops a formal and systematic methodology for efficient mapping of several contemporary artificial neural network (ANN) models on k-ary n-cube parallel architectures (KNC's). We apply the general mapping to several important ANN models including feedforward ANN's trained with backpropagation algorithm, radial basis function networks, cascade correlation learning, and adaptive resonance theory networks. Our approach utilizes a parallel task graph representing concurrent operations of the ANN model during training. The mapping of the ANN is performed in two steps. First, the parallel task graph of the ANN is mapped to a virtual KNC of compatible dimensionality. This involves decomposing …
Studies Of The Morphology And Dynamics Of Flame-Generated Agglomerates Using Dynamic Light Scattering., Glenn Michael Waguespack
Studies Of The Morphology And Dynamics Of Flame-Generated Agglomerates Using Dynamic Light Scattering., Glenn Michael Waguespack
LSU Historical Dissertations and Theses
Accurate determination of the morphology and dynamics of aerosols consisting of agglomerated sub-micron sized particulates is needed for soot formation studies, process monitoring in flame-based materials synthesis applications, and pollution control studies. The objective of the current study is to investigate the application of dynamic light scattering (DLS) to flames as an extension of current measurement technologies. Unlike previous DLS flame studies, conventional polarized DLS is supplemented with depolarized DLS measurements to account for the agglomerates' anisotropy. Because unavailable relationships between the agglomerates' morphological parameters and the Brownian translational and rotational diffusion coefficients under non-continuum conditions are required for accurately …
Removal Of Hydrophobic Organic Compounds And Surfactants From Wastewater: Polyaphron-Enhanced Solvent Extraction And Biodegradation., Chunlong Zhang
Removal Of Hydrophobic Organic Compounds And Surfactants From Wastewater: Polyaphron-Enhanced Solvent Extraction And Biodegradation., Chunlong Zhang
LSU Historical Dissertations and Theses
Surfactant based processes are emerging and becoming increasingly important in pollution control. A novel predispersed solvent extraction (PDSE) technique using surfactant based colloidal liquid aphrons (CLAs or polyaphrons) and colloidal gas aphrons (CGAs) for the removal of hydrophobic organic compounds (HOCs) from the aqueous phase was studied. The process involves an extraction of HOCs into CLAs, followed by a flotation using CGAs. Polyaphrons were characterized by a particle size analyzer. The size distribution was found to be bimodal. The effects of surfactant types, surfactant concentrations and storage times on the size distribution were studied. Polyaphrons have long shelf-lives and are …
Performance And Analysis Of Segmented Multiple Bus Systems., Jungjoon Kim
Performance And Analysis Of Segmented Multiple Bus Systems., Jungjoon Kim
LSU Historical Dissertations and Theses
The dissertation introduces a new class of bus-based systems called the Segmented Multiple Bus System (SMBS). One of the unique characteristics of the SMBS is that it allows the exploitation of memory reference locality even though it is a bus-based nondirect network. This comes from the architectural interconnection feature that the SMBS can be viewed as a large-scale multiple bus system (MBS) that has been partitioned into smaller partitions called segments. Each such segment is in effect a small conventional MBS whose size is chosen so as to avoid bus loading problems. The SMBS overcomes the architectural limitations of bus-based …
Gravity-Assisted Tertiary Gas Injection Process In Water-Drive Oil Reservoirs., Bogdan Lepski
Gravity-Assisted Tertiary Gas Injection Process In Water-Drive Oil Reservoirs., Bogdan Lepski
LSU Historical Dissertations and Theses
In dipping, water-drive reservoirs, substantial incremental oil can be produced using gravity-assisted gas injection improved recovery processes. These processes include the Double Displacement Process (DDP) and the Second-Contact Water Displacement (SCWD). The efficiency of these processes depends, in part, on phase distribution in the pore space after gas injection which in turn depends on interfacial and surface tensions (IFT) of the phases involved. The research described here-in pertains to experimental work performed to investigate various aspects of the DDP and the SCWD in both homogenous and heterogeneous rock types with dead oil/nitrogen and recombined-oil/methane fluid systems. Additional work was performed …
An Integrated Gps-Gis Methodology For Performing Travel Time Studies., Cesar A. Quiroga
An Integrated Gps-Gis Methodology For Performing Travel Time Studies., Cesar A. Quiroga
LSU Historical Dissertations and Theses
This dissertation describes a methodology for conducting travel time studies based on global positioning system (GPS) receivers and geographic information system (GIS) technology. Compared to traditional approaches, the new methodology provides consistency, automation, finer levels of resolution, and better accuracy in measuring travel time and speed. These characteristics enable the detection of localized traffic effects much more efficiently than with traditional techniques. The new methodology automates the data collection and data reduction procedures, and provides improved procedures for documenting and analyzing travel time and speed data. As a result, large amounts of reliable travel time and speed data can be …
A Theory Of Cortical Neural Processing., David Timothy Young
A Theory Of Cortical Neural Processing., David Timothy Young
LSU Historical Dissertations and Theses
This dissertation puts forth an original theory of cortical neural processing that is unique in its view of the interplay of chaotic and stable oscillatory neurodynamics and is meant to stimulate new ideas in artificial neural network modeling. Our theory is the first to suggest two new purposes for chaotic neurodynamics: (i) as a natural means of representing the uncertainty in the outcome of performed tasks, such as memory retrieval or classification, and (ii) as an automatic way of producing an economic representation of distributed information. We developed new models, to better understand how the cerebral cortex processes information, which …
A Computer Automated, Hydraulically Integrated Serial Turbidostat Algal Reactor (Histar): Mathematical Modeling And Experimental Analysis., Chandra Sekhar Theegala
A Computer Automated, Hydraulically Integrated Serial Turbidostat Algal Reactor (Histar): Mathematical Modeling And Experimental Analysis., Chandra Sekhar Theegala
LSU Historical Dissertations and Theses
Conceptually, the Hydraulically Integrated Serial Turbidostat Algal Reactor (HISTAR) has two components: (1) sealed turbidostats for producing a high quality algal inoculum, and (2) a series of unprotected inter-connected continuous flow stirred tank reactors (CFSTRs) for mass producing algae under approximated plug flow conditions. The hydraulic retention time of each individual CFSTR ($\theta\sb{\rm n})$ is set low enough (dilution is set high) that any suspended organisms (both contaminants and desired algae) entering the CFSTR would be washed to the next CFSTR well within their doubling time. However, as the turbidostats are employed to inoculate the first CFSTR on an almost …
Feedback Linearizing Control Strategies For Chemical Engineering Applications., Michael James Kurtz
Feedback Linearizing Control Strategies For Chemical Engineering Applications., Michael James Kurtz
LSU Historical Dissertations and Theses
Two widely studied control techniques which compensate for process nonlinearities are feedback linearization (FBL) and nonlinear model predictive control (NMPC). Feedback linearization has a low computational requirement but provides no means to explicitly handle constraints which are important in the chemical process industry. Nonlinear model predictive control provides explicit constraint compensation but only at the expense of high computational requirements. Both techniques suffer from the need for full-state feedback and may have high sensitivities to disturbances. The main work of this dissertation is to eliminate some of the disadvantages associated with FBL techniques. The computation time associated with solving a …
Tribological Behavior Of Duplex Nitrogen Diffusion/Dlc Coating Treatments., Yan Liu
Tribological Behavior Of Duplex Nitrogen Diffusion/Dlc Coating Treatments., Yan Liu
LSU Historical Dissertations and Theses
Diamond-like carbon (DLC) coatings have high potential for developing advanced tribological systems and the overall objective of the present research is to provide a framework to theoretically design and experimentally develop and study such systems of interest. The present research concentrates on the following specific aspects: the fundamental wear mechanism of DLC coatings; finite element (FE) modeling to understand the stress distribution in coating/substrate system under indentation and friction; and the influence of graded interface on the tribological behavior of DLC coatings. The experimental results showed that DLC films possess low friction coefficient ($f\sb{init}$: 0.12-0.20, $f\sb{fin}$: 0.06-0.08) and low wear …
Coastal Restoration Using Pipeline-Conveyed Sediments., Catherine Faith Voisin
Coastal Restoration Using Pipeline-Conveyed Sediments., Catherine Faith Voisin
LSU Historical Dissertations and Theses
A spreadsheet program was successfully developed which determines the engineering requirements for pipeline transport of sediments from dredge sites to wetland restorations sites. The program called SLURRY.XLS involves several new correlations. A new correlation for determining the critical velocity of particle transport is presented. New correlations were statistically developed for determining the drag coefficient of particles. The spreadsheet also successfully determines settling velocities of the individual particle sizes in any settling regime. A second spreadsheet program entitled "CONSOL.XLS" uses geotechnical principles of consolidation for determining marsh surface elevation with and without hydraulic fill versus time. The CONSOL.XLS program permits the …
Performance Of Composite Piping Systems: Thermal, Fire Endurance, And Joining Characteristics., Michael Andre Stubblefield
Performance Of Composite Piping Systems: Thermal, Fire Endurance, And Joining Characteristics., Michael Andre Stubblefield
LSU Historical Dissertations and Theses
Composite piping systems are becoming the "System of Choice" in many applications previously the domain of metallic piping systems. For full acceptability and usage of these composite piping systems, new innovative approaches must be developed. Three areas of development are addressed; (i) thermal efficiency, (ii) fire endurance, and (iii) joining techniques. In the development of the energy conserving composite pipe, the thermal contact resistance acts as an additional insulating layer. A model and device to predict and measure the contact resistance for a pipe system has been developed. A corrugated layer, which acts as an enhanced contact resistance layer, forms …
A Study Of The Effect Of Energetic Flux Bombardment On Intensified Plasma-Assisted Processing., Albert Amatey Adjaottor
A Study Of The Effect Of Energetic Flux Bombardment On Intensified Plasma-Assisted Processing., Albert Amatey Adjaottor
LSU Historical Dissertations and Theses
An investigation of the plasma nitriding mechanism under intensified conditions (average particle energy up to 1200 eV) was carried out using a triode configuration. The significance of the different physical processes taking place during intensified plasma nitriding, such as sputtering, implantation, defect generation, redeposition and diffusion were investigated experimentally, while theoretical predictions were obtained by using the TRIM (transport of ions in matter) code. A titanium-base alloy was selected as the substrate material. Sputtering yield in an inert atmosphere was found to exhibit three regimes as a function of incoming particle energy. The low energy and high energy regimes were …
Development Of A Prototype Computer-Assisted Well Control System For Deep Ocean Drilling Environments., Orville Allen Kelly
Development Of A Prototype Computer-Assisted Well Control System For Deep Ocean Drilling Environments., Orville Allen Kelly
LSU Historical Dissertations and Theses
An advanced prototype computer-assisted deep water drilling well control system was developed using process control technology. The goal of the system was to improve rig safety by reducing the potential for surface and underground blowouts through providing enhanced bottom hole and casing seat pressure control during the well kill process. The system developed is capable of full computer control of the fluid pump and drilling choke control functions during normal well control operations. The system provides computer-assistance in collecting and curve fitting slow circulation rate pump pressure data, in developing a well kill program (kill sheet), and in detecting anomalies …
Feasibility Study On The Reduction Of Hydrostatic Pressure In A Deep-Water Riser Using A Gas-Lift Method., Clovis Antonio Lopes
Feasibility Study On The Reduction Of Hydrostatic Pressure In A Deep-Water Riser Using A Gas-Lift Method., Clovis Antonio Lopes
LSU Historical Dissertations and Theses
Recent successful exploration efforts in deep waters have heightened interest in developing oil and gas reservoirs on the continental slope. Leases have been obtained in water depths up to 10,000 ft with a requirement that they be drilled within the next decade. Use of current techniques to drill these leases will require extremely large floating drilling units and large diameter marine riser systems. This study presents the results of a feasibility study on the use of an automated gas-lift system for a marine riser that will maintain the hydrostatic pressure in the subsea well-head equal to that of the sea …
Cellulose-Reinforced Composites And Srim And Rtm Modeling., Mohammad Fahrurrozi
Cellulose-Reinforced Composites And Srim And Rtm Modeling., Mohammad Fahrurrozi
LSU Historical Dissertations and Theses
Structural reaction injection molding (SRIM) cellulosic/polyurethane composites were prepared from various forms of cellulosic mats, and elastomeric polyurea-urethane (PUU) and rigid polyurethane (PU) formulations. Mats (woven and non-woven) prepared from different sources of fibers with lignin content ranging from zero (cotton) to at least 10% (sugar cane and kenaf fibers) performed comparably in PUU/cellulosic composites. Young's modulus and tensile strength of PUU/cellulosic composites were doubled with 5% and 7% fiber loading respectively. Young's modulus and tensile strength of PU/cellulosic composites were improved by 300% and 30%, respectively, with 7% fiber loading, whereas their bending moduli and strengths were improved up …
Optimization And Scale-Up Of Thiarubrine A Production From Hairy Root Cultures Of Ambrosia Artemisiifolia., Santosh G. Bhagwath
Optimization And Scale-Up Of Thiarubrine A Production From Hairy Root Cultures Of Ambrosia Artemisiifolia., Santosh G. Bhagwath
LSU Historical Dissertations and Theses
Thiarubrine A (TA), a plant secondary metabolite synthesized by members of the family Asteraceae possesses antifungal and antiviral properties and is a potential pharmaceutical. The objective of the work was the optimization and scale-up of a bioprocess for the production of TA using hairy root cultures of Ambrosia artemisiifolia. At the inception of the work an established hairy root culture of the model system was used as inoculum in reactor experiments for the development of a protocol for the quantification of TA and in subsequent shake flask experiments to determine optimum culture conditions. TA accumulation closely paralleled growth and then …
Coupled Field Equations For Saturated Soils And Its Application To Piezocone Penetration And Shield Tunneling., Murad Yusuf Abu-Farsakh
Coupled Field Equations For Saturated Soils And Its Application To Piezocone Penetration And Shield Tunneling., Murad Yusuf Abu-Farsakh
LSU Historical Dissertations and Theses
An elasto-plastic coupled system of equations are formulated here in order to describe the time-dependent deformation of saturated cohesive soils. Formulation of these equations is based on the principle of virtual work and the theory of mixtures for inelastic porous media as proposed by Prevost (1980) and Kiousis and Voyiadjis (1988). The saturated soil is considered as a mixture consisting of two deformable media, the solid grains and the water. Each medium is regarded as a continuum and follows its own motion. The coupled equations are developed for large deformations with finite strains in an updated Lagrangian reference frame. The …
Stochastic Techniques For The Solution Of Electrostatic Problems With Applications To Electron Optics., Elias Kougianos
Stochastic Techniques For The Solution Of Electrostatic Problems With Applications To Electron Optics., Elias Kougianos
LSU Historical Dissertations and Theses
We apply stochastic techniques towards the solution of the two-dimensional Laplace's equation in boundary value problems encountered in the calculation of electrostatic potentials in electron lenses and deflectors. The justification of these techniques arises from an astonishingly simple but far-reaching principle, which has been known for a long time but has been rarely used: the potential at any point in the interior of a charge-free region can be calculated by performing random walks starting at this point and terminating at the boundary of the region--the potential is then the average of the potential boundary values (assumed known) over the random …
Chemical Vapor Deposition Of Copper Films., Narendra Shamkant Borgharkar
Chemical Vapor Deposition Of Copper Films., Narendra Shamkant Borgharkar
LSU Historical Dissertations and Theses
We have studied the kinetics of copper chemical vapor deposition (CVD) for interconnect metallization using hydrogen (H$\sb2$) reduction of the Cu(hfac)$\sb2$ (copper(II) hexafluoroacetylacetonate) precursor. Steady-state deposition rates were measured using a hot-wall microbalance reactor. For base case conditions of 2 Torr Cu(hfac)$\sb2$, 40 Torr H$\sb2$, and 300$\sp\circ$C, a growth rate of 0.5 mg cm$\sp{-2}$ hr$\sp{-1}$ (ca. 10 nm min$\sp{-1}$) is observed. Reaction order experiments suggest that the deposition rate passes through a maximum at partial pressure of 2 Torr of Cu(hfac)$\sb2$. The deposition rate has an overall half-order dependence on H$\sb2$ partial pressure. A Langmuir-Hinshelwood rate expression is used to …
Feature-Based Models For Three-Dimensional Data Fitting., Gregory Todd Dobson
Feature-Based Models For Three-Dimensional Data Fitting., Gregory Todd Dobson
LSU Historical Dissertations and Theses
There are numerous techniques available for fitting a surface to any supplied data set. The feature-based modeling technique takes advantage of the known, geometric shape of the data by deforming a model having this generic shape to approximate the data. The model is constructed as a rational B-spline surface with characteristic features superimposed on its definition. The first step in the fitting process is to align the model with a data set using the center of mass, principal axes and/or landmarks. Using this initial orientation, the position, rotation and scale parameters are optimized using a Newton-type optimization of a least …
Numerical Simulation Of Geosynthetic Reinforced Earth Structures Using Finite Element Method., Surajit Pal
Numerical Simulation Of Geosynthetic Reinforced Earth Structures Using Finite Element Method., Surajit Pal
LSU Historical Dissertations and Theses
Geosynthetics are widely used as reinforcements in various earth structures. Current design methods are based on some simplified assumptions and are primarily modified versions of limit equilibrium methods used in design of the unreinforced earth structures. All of these design methods are conservative and result in uneconomical design. The best method for verifying the design assumptions and studying the stress-deformation behavior of geosynthetic reinforced earth structures is by constructing a series of large scale test walls with adequate instrumentation and collecting data from them. But the cost involved in such a scheme precludes undertaking this kind of study. Thus Numerical …
Determination Of Hydrocarbon Type From The Dual-Spaced Neutron Tool Responses., Luis Fernando Quintero
Determination Of Hydrocarbon Type From The Dual-Spaced Neutron Tool Responses., Luis Fernando Quintero
LSU Historical Dissertations and Theses
A new interpretation method that allows for the determination of the fluid type present in a formation of interest was developed. The new method is referred to as the "Three Neutron Porosity Log". The method is based on an algorithm that determines three apparent neutron porosities. These porosities, derived from the raw counts of the dual-spaced neutron tool, have three different radii of investigation. All three neutron porosities, near, far, and ratio, when properly calibrated read the true porosity in water-bearing zones. In oil or gas-bearing zones the mud filtrate invasion profile will cause the three apparent neutron porosities to …
Injection Of Species Under Electrical Field To Enhance Bioremediation., Fazle Rabbi
Injection Of Species Under Electrical Field To Enhance Bioremediation., Fazle Rabbi
LSU Historical Dissertations and Theses
Electrokinetics is one of the most viable alternatives for injecting/extracting water, organic and ionic species in low permeability soils as well as heterogeneous media because the transport processes are independent of the pore sizes. A better understanding of the principles offers the opportunity to employ multi-component species transport under electrical fields to inject electron acceptors, nutrients and other process additives for enhancement of in-situ bioremediation in low permeability and heterogeneous media. This study assesses the potential to employ and exploit the principles of multi-component species transport under electrical fields as mean to supplement, enhance and engineer in-situ bioremediation. It was …
Evaluation Of Alternative Gases For Immiscible Cyclic Injection., Sara Shayegi
Evaluation Of Alternative Gases For Immiscible Cyclic Injection., Sara Shayegi
LSU Historical Dissertations and Theses
Cyclic gas injection processes have been primarily restricted to the use of pure CO$\sb2$ or CO$\sb2$ that has been slightly contaminated with reservoir gases. However, it is difficult to employ CO$\sb2$ in certain circumstances due to transport, economic, or corrosion problems. This study presents the results of laboratory investigations of the cyclic gas injection process using methane, nitrogen and combinations of these gases with CO$\sb2$. Cyclic gas injections were performed at immiscible conditions in consolidated sandstone cores that contained waterflood residual oil under analogous conditions to previous cyclic CO$\sb2$ injections for comparative purposes. Pure methane recovered approximately the same amount …
Linear Matrix Inequality Approach To Robust Emergency Lateral Control Of A Highway Vehicle With Time-Varying Uncertainties., Robert Edward Benton Jr
Linear Matrix Inequality Approach To Robust Emergency Lateral Control Of A Highway Vehicle With Time-Varying Uncertainties., Robert Edward Benton Jr
LSU Historical Dissertations and Theses
New linear-matrix-inequality (LMI) based methods are developed for the static-output-feedback stabilization and reduced-gain static-output-feedback stabilization of time-invariant systems. Unlike previous methods, the static-output-feedback method is non-iterative in LMI solutions. The methods are extended to design robust static-output-feedback controllers for time-varying systems using a polytopic-systems approach. Examples are given which demonstrate the use of each of the new methods. The specific problem of emergency lateral control of a highway vehicle is then addressed using the new robust static-output-feedback method. A controller is designed which robustly stabilizes the vehicle over the range of highway speeds (15 to 30 m/s) and a range …
Development Of Thin Gold Film Thermal Sensors For Synchrotron X-Ray Exposure Diagnostics., Harish M. Manohara
Development Of Thin Gold Film Thermal Sensors For Synchrotron X-Ray Exposure Diagnostics., Harish M. Manohara
LSU Historical Dissertations and Theses
High aspect ratio lithography utilizes high intensity exposure sources, such as synchrotron storage rings, to deposit sufficient dose in the resist to produce a successful pattern transfer. Such highly powerful sources are known to cause undesirable thermal effects in the mask-resist-substrate system. Hence, the measurement of temperature of a mask-resist-substrate system during irradiation is an important exposure diagnostic feature. Deposition of a reasonably accurate dose in the resist is controlled by knowledge of the exposure source intensity. Periodic monitoring of the synchrotron radiation beam power and its spatial distribution at the exposure plane is necessary. In this research, diagnostic techniques …
Wood Fiber Reinforced Polypropylene Composites., Minqiu Lu
Wood Fiber Reinforced Polypropylene Composites., Minqiu Lu
LSU Historical Dissertations and Theses
Mechanical properties of polypropylene (PP)/wood fiber composites depend not only on the properties of each primary component but also on a complex interaction of several factors such as fiber loading and size, characteristics of fiber-polymer matrix interface, and the processing conditions. Both sequential and simultaneous composites are formulated in this research. First, sequential composites are made by compounding wood fibers with PP in the presence of maleated polypropylene (MPP) as a coupling agent in a twin-screw extruder. A small amount of MPP (1 wt%) present in these sequential composites can increase the tensile strength of the composites significantly. The tensile …
Acid Solubilization Of Fish Protein For Production Of Protein Hydrolysate., Ercument Ozer
Acid Solubilization Of Fish Protein For Production Of Protein Hydrolysate., Ercument Ozer
LSU Historical Dissertations and Theses
The mechanism of fish protein solubilization by acid hydrolysis at elevated temperatures was investigated. Rate expressions for the solubilization were determined using pilot scale data with two different rate determination methods. A postulated mechanism was verified and estimated rates were evaluated on five independent verification experiments. A functional relationship between nonprotein byproduct concentration and whiteness of fish protein hydrolysate (FPH) was developed. Initial and set-point operating variables were calculated to produce FPH with acceptable color characteristics for food use. A batch reactor was used for duplicate hydrolysis trials conducted at three acid and three temperature levels for four hours. Samples …
Cost Analysis And Air Pollution Impact Of Electric Vehicles On A Metropolitan Area., Hector David Arias-Varela
Cost Analysis And Air Pollution Impact Of Electric Vehicles On A Metropolitan Area., Hector David Arias-Varela
LSU Historical Dissertations and Theses
During the 1990's, increasing attention has been paid to electric vehicles (EV's) because of their potential to reduce air pollution in metropolitan areas such as the Los Angeles Metropolitan Area in the U.S., Mexico City and Its Metropolitan Area in Mexico, Greater London in the United Kingdom and other urban areas. However, few studies to determine the costs and benefits of reducing air pollution by introducing EV's into these mega cities have been carried out. A model to determine the marginal costs and environmental impact of electric vehicles on a metropolitan area is designed in this study. The model simulates …