Digital Commons Network^™

Aqueous Phase Oxidation Of Organics (Wet-Air, Vapor-Liquid Equilibrium, Synergism, Free Radical, Xylene, Phenol)., Richard Scott Willms

LSU Historical Dissertations and Theses

Fundamental disappearance kinetics parameters have been obtained for four compounds individually subjected to aqueous phase oxidation. These four compounds are m-xylene, phenol, tetrachloroethylene, and malathion. Concentration histories were obtained using a one liter "sampled-batch" reactor. Reaction conditions ranged from 114-290 (DEGREES)C and 1000-2500 psi air. A kinetics model incorporating vapor-liquid equilibrium effects was developed and used to determine reaction rate constants. The reactions were found to be first order in organic and 1/2 order in oxygen. Induction periods were observed for m-xylene and phenol. The durations of these periods were found to be inversely proportional to oxygen concentration. Activation energies …

Hydrodynamic Characteristics And Coal Combustion Modeling Of A High Velocity Fluidized Bed (Solids Friction Factor, Two Phase Flow, Pressure Profile, Fast), Ronald Wayne Breault

Doctoral Dissertations

A Loop Fluidized Bed (LFB) based on the fast fluidization concept is a novel method for effective solid-gas contact and can play an important role in coal combustion. It can be operated under pressure making it eminently suited for the production of high temperature gas from coal for operating gas turbines for power generation. The LFB can operate over a wide range of gas flow rates and coal can be introduced at various points without excessive pressure drops. Further, it is possible to capture higher amounts of sulfur dioxide due to the use of fine dolomite or limestone particles. This …

Risk And Uncertainty (Utility, Decision), Paul Snow

Doctoral Dissertations

The conventional theory of decision making under risk relies on axioms that reflect assumptions about people's subjective attitudes towards wealth. The assumptions are unverifiable, and the axioms are too restrictive. They forbid some decision rules that a plausibly rational decision maker ("DM") could find useful.

A new method, at once less restrictive and less dependent upon subjective assumptions, motivates expected utility techniques by assuming that a DM wishes to place an upper limit on the probability of ruin. All bounded-above, increasing functions defined over a suitable domain can serve as utility functions.

Now, DM can evaluate lotteries according to their …

Studies Of Grain Boundary Structure And Annealing Behavior In Nickel Using Transmission Electron Microscopy (Tem, Dislocation)., An-Chich Chou Han

LSU Historical Dissertations and Theses

Transmission electron microscopy has been used to study grain boundary structure and dislocation reactions in annealed pure nickel sheets. In slightly annealed nickel, the dislocation content and distribution in grain boundaries were found to be random. After annealing at 800(DEGREES)C, a temperature within the recovery and recrystallization stage, the majority of grain boundaries contained periodic arrays of dislocations. The hexagonal dislocation networks with Burgers vectors of the type of a/6 were found in a large number of twin boundaries. The origin and the formation mechanisms of this configuration are discussed. The incorporation of absorbed lattice dislocations in the boundary during …

Life Table Construction From Population Age Distributions Suffering From Response Biases In Age-Reporting:A New Technique(Not Requiring Age Smoothing)With Application To Indian Census Age-Returns., Subrata Lahiri Dr.

Doctoral Theses

Preliminary concepts of life tables, its role in demographic analysis, a brief chronological review of various literature on the construction of life table starting from John Grants investigation on mortality, along with an introduction to the basic problem and objectives of the present study.Chapter II describes the concept and utility of cumulative census survival ratios, first introduced by Professors Ansley J. Coale and Paul Demeny (1967) as the ratio of the number of persons aged x+10 end above enumerated at time t+10 to the number of persons aged x and above enumerated at time t. These are compared to the …

On The Choice Of Shadow Prices For Project Evaluation., Jean Dreze Dr.

Doctoral Theses

Manohar athanna is one of the remotest parts of Jhalawar District (Rajasthan, India). In the month of June it offers a striking contrast of scenic beauty and economic destitution. Agricultural activity is at a virtual standstill. The soil is very arid, irrigation practically non-existent, and by then the villagers (many of them tribals) have resolved to wait upon the good will of the rain gods.. Hence they have very little to do, or at least so they believe. Some gather wood to sell it in Manohar, walking miles under the scorching sun for a meagre reward, and adding slowly but …

Pavement Thickness Designs Utilizing Low-Strength (Pozzolanic) Base And Subbase Materials, Gary W. Sharpe, Robert C. Deen, Herbert F. Southgate, Mark Anderson

Kentucky Transportation Center Research Report

This paper presents information whereby laboratory test data for pozzolanic base and subbase materials may be combined with elastic layer theory and a limiting strain criterion to determine thickness designs equivalent to conventional asphaltic concrete and crushed stone pavement structures. A summary of laboratory testing in Kentucky also is presented. An example thickness design determination is presented and includes an economic comparison of alternative designs with the conventional asphaltic – crushed stone thickness design.

A Study Of The Texture Measurement Definition Problem (Image Analysis)., Ramon Emilio Vasquez-Espinosa

LSU Historical Dissertations and Theses

The problem of texture measurement definition is studied. A theory is presented in order to overcome the problem. This theory includes a conceptual framework for the general measurement definition problem. This framework is based on the concepts of a perceptual transform, a perceptual space, a measurement transform and a similarity transform. Using this conceptual framework and a particular choice for the similarity transform, a set of requirements are defined. These requirements can be used to create a formal method for defining measurements off the GLC matrices. The formal procedure is based on preserving perceptual relationships among textures. To apply this …

Interactive Three Dimensional Computer Graphics Simulation Of The Kinematics Of The Human Thumb (Biomechanics, Functional Anatomy, Skeletal Kinematics)., William Leslie Buford Jr

LSU Historical Dissertations and Theses

This dissertation describes the development of a computer graphical simulation of thumb kinematics as a clinical design tool. The simulation utilizes a realistic data structure of the thumb bones, an optimized model of joint kinematics, and a variety of experimental cadaver measurements. It was developed with a concurrent processing arrangement in which graphical transformations and interactive manipulations are handled on a distributed graphics system, and musculoskeletal dynamics calculations are carried out on a minicomputer. The thumb simulation includes interactive entry of patient related data, simulation of two types of tendon transfer operations, calculation and display of resultant muscle mechanics during …

Rutting, A Case Study (Us 23, 1.5 Miles North Of Louisa), James H. Havens, Gary W. Sharpe, David L. Allen, Herbert F. Southgate

Kentucky Transportation Center Research Report

This case study of rutting in an asphaltic concrete pavement makes recourse to trenching full width and full depth to expose and observe the entire cross section of the structure. Rutting occurred in the vicinity of Station 59+00 on US 23, 1.5 miles north of Louisa, during August and September 1983 when traffic was diverted onto newly constructed northbound lanes (without final surface and shouldering) while excavation into the hillside was completed for the southbound lanes. Earth movers crossed the northbound lanes going to and from a waste area. Coal trucks (Figures 1 and 2) slowed, stopped, and crept where …

H & V News

Building Services Engineering

No abstract provided.

H & V News

Building Services Engineering

No abstract provided.

Scs Natinoal Engineering Handbook: Section 15, Irrigation, Chapter 12--Land Leveling, U.S. Department Of Commerce

All U.S. Government Documents (Utah Regional Depository)

Land leveling or land grading for irrigation is modifying the surface relief of a field to a planned grade to provide a more suitable surface for efficiently applying irrigation water. Normally land leveling requires moving a lot of earth over several hundred feet. This should not be confused with land planning, land smoothing, or land floating. They are usually accomplished with special equipment to eliminate minor irregularities, and they do not change the general topography of the land surface. Rough grading is removing knolls, mounds, or ridges and filling pockets or swales in a field that is not to have …

Across-Wind Response Of Slender Structures Of Circular Cross-Section To Atmospheric Turbulence, Roger Indranath Basu

Digitized Theses

A mathematical model which yields estimates of across-wind response is presented. Fluctuating forces from three sources are identified and modeled. They are forces due to vortex shedding, forces induced by the lateral component of turbulence and forces induced by motion. The motion dependent force, which in reality is a complex flow-structure interaction phenomenon, is incorporated in the model through a simple device. The model is semi-empirical in construction, and relies on the results from laboratory-scale experiments for the empirical component.;The reliability of the predictions depends not only on the fidelity of the mathematical model but also on the quality of …

Effects Of Rotary Inertia And Shear Deformation On Extensional Vibrations Of Continuous Circular Curved Beams, Mohamed El-Said Said Issa

Doctoral Dissertations

This dissertation is devoted to the dynamic analysis of continuous circular curved beams. The dynamic stiffness matrix is derived for the determination of natural frequencies of continuous curved beams undergoing in-plane vibrations. The formulation of stiffness matrix may be widely applied to problems with various consideration of Bernoulli-Euler Theory, Rayleigh Theory and Timoshenko Theory. Using this formulation for dynamic loading, the fixed-end moment, shear and thrusts for concentrated and distributed loads have been derived. Two continuous circular curved beams subjected to free and forced vibrations are given to illustrate the application of the proposed method and to show the effects …

Strain Energy Analysis Of Pavement Designs For Heavy Trucks, Herbert F. Southgate, Robert C. Deen, Jesse G. Mayes

Kentucky Transportation Center Research Report

The first portion of this paper summarizes classical concepts of work, or strain energy, as applied to the analysis of stresses, strains, and deflections under various vehicular load configurations on pavement systems. Controlling equations for strain energy density are presented. When considering strain energy density, strain energy, or work, all components of stresses or strains must be taken into account so that total internal behavior can be evaluated. Previously, pavement thickness design systems have been developed using only a single component of strain, typically at the bottom of the asphaltic concrete layer or at the top of the subgrade. Strain …

H & V News

Building Services Engineering

No abstract provided.

H & V News

Building Services Engineering

No abstract provided.

The Coupling Of Monte Carlo Integration With The Boundary Integral Equation Technique To Solve Poisson Type Equations., Gary Steven Gipson

LSU Historical Dissertations and Theses

The primary topic of this work is a method for dealing with boundary element formulations of nonhomogeneous terms in Poisson type equations. A concise presentation of boundary integral techniques and the corresponding fundamental solutions plays an important role in this development. Using Monte Carlo quadrature theory, an algorithm for the construction of a two-dimensional BEM Poisson equation analyzer is derived. A FORTRAN program based upon this algorithm is presented as a novel device that solves the general Poisson equation in two-dimensional and axisymmetric geometries without domain discretization. In the axisymmetric case, Monte Carlo integration is also used to effectively compute …

Analysis Of The Instability Of Laminar, Newtonian Liquid Jets In Air., Warren Thorne Abbott

LSU Historical Dissertations and Theses

This dissertation results from an investigation into the instability of free jets of a Newtonian liquid (water) in air which are produced from long nozzles and have initially parabolic velocity profiles. This work includes an experimental investigation into both the jet length and the drop formation of such jets. This work also includes a numerical solution of the momentum equations in cylindrical coordinates. From the experimental work, a modification to existing theoretical equations has been made to account for the existance of local maxima in the length of laminar jets as their velocity is increased. An addition to the modification …

Adaptive Feedforward Control Of Wastewater Neutralization., Richard Albert Balhoff

LSU Historical Dissertations and Theses

The purpose of this dissertation is to show the development and testing of an adaptive feedforward control of a wastewater neutralization process. The adaptive controller is compared to a nonlinear proportional-integral-derivative (NPID) controller developed by Shinskey (1970). The process and controllers were simulated digitally. The adaptive controller utilizes two pH probes, a feedforward probe and a feedback probe (this measurement is used in the adaptive gain calculation). The feedback measurement provides the adaptive controller with a form of reset action. Probe noise and lag, valve hysteresis and lag, and dead time were included in the simulation. The process simulated for …

Nonuniformly And Randomly Sampled Systems, George Dimitrios Kontopidis

Doctoral Dissertations

Problems with missing data, sampling irregularities and randomly sampled systems are the topics covered by this dissertation.

The spectral analysis of a series of periodically repeated sampling patterns is developed. Parameter estimation of autoregressive moving average models using partial observations and an algorithm to fill in the missing data are proved and demonstrated by simulation programs. Interpolation of missing data using bandlimiting assumptions and discrete Fourier transform techniques is developed. Representation and analysis of randomly sampled linear systems with independent and identically distributed sampling intervals are studied. The mean, and the mean-square behavior of a multiple-input multiple-output randomly sampled system …

Predicting The Formation Of Condensation Ash From Coal Combustion, Shu-Mu Hsieh

Doctoral Dissertations

This study predicts the nature of condensation ash formed from direct combustion of coal. Three coal-fire combustors, a cyclone-fired (CF) boiler, a pulverized-fuel (PF) and a drop tube (DT) furnace were considered.

Predictions were based on the hypothesis that condensation ash is formed through two consecutive steps: vaporization and recondensation. Metal-containing species in coal are believed to vaporize during high temperature combustion. These vapors then diffuse and condense at the bulk gas phase.

The amount of metal-related vapor transport to the bulk gas phase is dictated by char surface composition which is, in turn, determined by the temperature history of …

Implementation Of Road Rater Deflection Testing For Pavement Evaluation And Overlay Design, Gary W. Sharpe, Herbert F. Southgate, Robert C. Deen

Kentucky Transportation Center Research Report

Road Rater deflection data were used to estimate the in-place subgrade strength and the in-place structural capacity of existing pavements. Pavement behavior can be expressed in terms of a reduced thickness of "reference" quality paving materials or as a reduced modulus of elasticity for the constructed thickness of asphaltic concrete. Mathematical relationships were developed making it possible to "program" the evaluation procedure (in modular form) for use with small hand calculators or minicomputers.

The pavement evaluation method has been successfully implemented in making recommendations for overlay designs for several pavement sections. Road Rater deflection data were used to estimate the …

Transient Inelastic Thermal Stresses In A Solid Cylinder With Temperature Dependent Properties., Habib Pour-Mohamadian

LSU Historical Dissertations and Theses

Transient temperature distribution in an infinitely long solid cylinder initially at uniform temperature T(,0), subjected to an axisymmetric thermal boundary condition, (immersed in an infinite medium of zero temperature) has been obtained. The mechanical properties of the material are considered to be temperature dependent. Using the available experimental data, an equation for each mechanical property as a function of temperature is obtained. Then, using a numerical method the corresponding transient and residual thermal stresses in a long solid cooling cylinder subjected to a transient axisymmetric temperature distributions are calculated. The residual stresses obtained indicate the same pattern with good agreement …

Numerical Gas Dynamics Of Internal And External Flows In Gun Barrels., Oktay Baysal

LSU Historical Dissertations and Theses

A computational combined solution to the internal and external flows in gun barrels is devised. A computer code, IEFLOW, is constructed to carry out all the calculations and present a complete package of tables and graphs of the physical property histories. With the input of the initial conditions at the threshold of the barrel, the internal and external flow fields and the simulation of blast is made possible. The flow inside the barrel, which is unsteady, compressible and one dimensional, is solved by a predictor-corrector technique using the method of characteristics. A two step, explicit, finite difference scheme is used …

Numerical Modeling Of The Internal Ballistics Of A Gas Gun., Ameziane Harhad

LSU Historical Dissertations and Theses

A numerical procedure is applied to three principal flow models of a gas gun, the discharge chamber, the main chamber, and the barrel chamber. In the first two models, an explicit method, the second order MacCormack scheme, is used to solve the Navier-Stokes equations for two-dimensional (axisymmetric), time dependent, compressible flow. The fluid is assumed to be a perfect gas. The flow boundaries may be arbitrary curved and time dependent. Transformations have been used to map the physical space into a computational space with uniform grid spacing. A grid generation surface has been achieved for various wall shapes. The third …

H & V News

Building Services Engineering

No abstract provided.

Natural Convection, Two-Phase Flow, And Crystallization In A Vacuum Pan Sugar Crystallizer., Jack Jerome Bunton

LSU Historical Dissertations and Theses

A mathematical model of a Vacuum Pan Sugar Crystallizer is developed. This mathematical model is based on the fundamentals of the physics of two-phase flow. Because of the complexity of the model, the time dependent solution is accomplished using numerical methods designed to be executed by a digital computer. The model generates velocity, pressure, temperature, and supesaturation profiles for the Pan, in response to the operating conditions and the design of the Pan. The motivation for the development of this model is to give an analytical tool to study the effects of Pan design, control systems, and operating conditions on …

Methane Production From Alkaline Food Waste., Wilson Thomas Gautreaux Jr

LSU Historical Dissertations and Theses

Anaerobic digestion of an alkaline food waste for methane production was investigated. The waste generated by potato processing contained significant quantities of carbohydrate degradation products and sodium carbonate. Anaerobic digestion was determined to be a reliable process for waste treatment and methane production. The high sodium levels did not inhibit anaerobic digestion at a substrate concentration of 1.0 wt % alkaline peel solids. Single and two-stage (separate acid, methane stages) anaerobic digestion systems were studied. In two-stage bench-scale studies at 37(DEGREES)C, methane production averaged 0.28 m('3)/kg COD feed or 0.65 m('3)/(m('3)(.)d) in a settled bacterial sludge methane fermenter with a …