Digital Commons Network^™

Development Of A Computer-Integrated Manufacturing Simulation Model: A Hybrid Systems Approach., Vinay Kumar Vasudev

LSU Historical Dissertations and Theses

The key to the successful "factory of the future" will be the effective coordination of managerial functions and production operations. The research presented in this dissertation addresses this "coordination" issue, especially in terms of understanding the impact and possibilities which exist in an information-rich environment. Such an environment is often referred to in the literature as being a computer-integrated manufacturing (CIM) environment. An interactive simulation modeling program, MOSES (Manufacturing Organization Simulation and Evaluation System), was developed for the purpose of describing, analyzing, and understanding such manufacturing. MOSES is a copyrighted computer program, a menu-driven, interactive, simulation modeling tool. MOSES users …

Online Detection And Estimation Of Parameter Jumps., Fahmida Nilufar Chowdhury

LSU Historical Dissertations and Theses

In many dynamic systems, the parameters are subject to jumps at unknown points in time. The jumps may be the result of some change in the operating system, or plant failure. In this work a method has been developed for fast detection of these jumps and estimation of the post-jump values. The proposed method is called the Combined Filter Algorithm. It is based on the conventional Kalman filter. Single-sample hypothesis test is used to determine the presence or absence of jumps. Small jumps, missed by the hypothesis test, are traced by a Random Walk Model Kalman filter. This is made …

Studies On Optimality Of Some Classes Of Designs., Rita Saharay Dr.

Doctoral Theses

la. General Dbaervations and Literature ReviewExperimentation playe an easential role in moet of the atatistioal investigations carried out for drawing inferences about certain unknown parametera of interest. If the eituation allowe for only one experiment to be executed out of a number of available alternative experiments, the experimenter ehould sim at perfoming the one which le optimum in This ie how the problem of ohooeing the beet experiment some sense. comes up.To judge the relative performances of various statistical exf mente, Blackwell (1951, 1953) and Blackwell and Girahiok (1954) introduced the concopt of sufficient experiments . However, in the ontext …

A Pseudoadiabatic Catalytic Reactor For The Conversion Of Methanol To Hydrocarbons, Alberto Ravella

Digitized Theses

The Pseudoadiabatic Operation (PO) of a fixed-bed catalytic reactor is an operating regime in which the temperature profile is monotonically increasing with the axial coordinate. It can be achieved in co-currently cooled reactors where the heat transfer fluid is a non-boiling liquid. This mode of operation has intrinsic advantages with respect to the hot-spot temperature profile usually experienced by packed bed units for exothermic reactions, such as better control of the temperature distribution and much less parametric sensitivity.;The PO was demonstrated experimentally for the first time in a pilot-plant-scale unit converting methanol to hydrocarbons.;Theoretical developments of the PO concept are …

Fluid Flow Within Porous Media, Greg Fischer

Honors Capstones

The objective of this project is to observe the flow of fluid within a saturated, rectangular, two-dimensional, porous media that is being heated from the side.

Simplified Analysis Of A Cladding-Frame Structural System, Nancy Marie Alberto

Doctoral Dissertations

This dissertation presents a simplified approach for the preliminary design and static analysis of a cladding-frame structural system subjected to concentrated, lateral loading conditions. The simplified approach, which utilizes the finite element analysis method, reduces the number of computations required for analysis of a structurally cladded frame to that of an architecturally cladded frame. This research develops a modified beam element to analytically replace a cladding panel element while retaining its structural benefits. The modified beam element is derived using a 16 degree of freedom isoparametric element and displacement correlations determined from the studies of a two-story, single bay frame …

Use Of Multiple Time Series Analysis To Forecast Maintenance Manhour Requirement For The Chemical Process Industry., Helen Bostock

LSU Historical Dissertations and Theses

It is hypothesized that chemical processing plant maintenance manhour requirement (the number of hours required to maintain a production facility at an optimal level) can be forecast. The hypothesis is supported by (1) a study of the independent variables which may impact the dependent variable, maintenance manhour requirement and (2) a comparative analysis of technological forecasting methods that suggested which methods might be most appropriate. Both econometric and statistical forecasting methods were considered. The philosophy inherent in each approach was recognized. A procedure for choosing a forecasting method to suit a given situation is outlined. Multiple time series analysis, supported …

The Rational Overhauser: An Interpolating Rational Cubic Curve., Jeffrey Neil Jortner

LSU Historical Dissertations and Theses

A rational interpolating cubic curve which implicitly maintains first order geometric continuity in splines has been developed. The curve is formed by blending two rational quadratic curves. Since the blending method used was originally introduced by Overhauser, this curve is referred to as the Rational Overhauser (Rover) curve. The curve formulation utilizes four shape factors to provide control of the curve. A geometrical and analytical interpretation of these shape factors and their relationship to each other is discussed. Procedures for representing conic sections using the rational Overhauser curve are presented. Also included are techniques for mapping between the Rover curve …

An Evaluation Of The Applicability Of Nonlinear Programming Algorithms To A Typical Commercial Process Flowsheeting Simulator. (Volumes I And Ii)., Michael Joseph Richard

LSU Historical Dissertations and Theses

An efficient methodology for using commercial flowsheeting programs with advanced mathematical programming algorithms has been developed for the optimization of operating plants. The methodology was demonstrated and validated using ChemShare Corporation's DESIGN/2000 simulation of the Freeport Chemical Company's plant for sulfuric acid manufacture and three nonlinear programming techniques; successive linear programming, successive quadratic programming and the generalized reduced gradient method. The application of this methodology begins with the development of a feasible base case simulation. Partial derivatives of the economic model and constraint equations are computed using fully converged simulations. This information is used to formulate an optimization problem which …

Borehole Friction Assessment And Application To Oilfield Casing Design In Directional Wells., Eric Edgar Maidla

LSU Historical Dissertations and Theses

The phenomenon of mechanical friction in the oil well borehole was investigated. Immediate application of such a study is to improve casing design in directional wells. An additional application is the prediction of reciprocating loads in directional wells for cementing purposes, that is recognized to be an effective method to avoid cement channeling through efficient mud displacement. Field studies on the borehole friction coefficient revealed its insensitivity to depth, various well trajectories, size of pipe and its surface configuration, leading to the conclusion that one value of the borehole friction factor can represent a single well. Also there was good …

Fail-Safe Local Area Networking Using Channel Redundancy., Ibibia Karisemie Dabipi

LSU Historical Dissertations and Theses

Local area networks represent a major development in data communications. The ring topology is the most popular of the local area networks. Its inherent problem, however, is the breakdown of the entire network in the event of a station failure resulting in total shut-down until repairs can be made. This dissertation is a study of designs for fail-safe local area networks. Two methods for maintaining the operation of a ring network are analyzed and compared. The first method uses a double-ring where the inner loop is optically coupled to the outer ring whenever a node failure occurs. The analysis performed …

Experimental And Finite Element Study Of Residual Stresses In Zircaloy-4(R) And Ofhc Copper Tubes., Jahangir Rasty

LSU Historical Dissertations and Theses

Non-homogeneous plastic deformation associated with metal-forming operations results in a state of residual stress in the final product. Complete evaluation of the mechanical behavior of the product under operating condition requires a knowledge of these stresses. In order to evaluate the magnitude and distribution of residual stresses, existing experimental techniques are complemented by computer-aided simulation of the forming process using elastic-plastic finite element method (FEM). It is found the FEM can be effectively utilized to simulate metal-forming operations in order to determine the combination of process variables which optimizes the residual stress distribution in the final product. In the experimental …

Stability And Stabilization Of The Wave Model., Masoud Shafiee

LSU Historical Dissertations and Theses

The stability properties of 2-D systems are an important aspect of the design of acoustic, seismic, image and sonar signal processors. This research utilizes the Wave model format to transport 1-D stability techniques to the 2-D setting. The research studies stability through multistep growth bounds on the Wave state. The use of Lyapunov theory is also considered. The research considers also the problem of stabilizing a 2-D system using state and/or output information feedback to interior and/or boundary controls. Finally the problem of observer design for 2-D systems is considered, with the new stability criteria being used to assure observer/system …

Fire Island Feasibility Study: Summary Report — Final Report, Uaa School Of Engineering

Reports

This document summarizes the findings the Fire Island Prison Feasibility Study, undertaken to assess the feasibility of locating a correctional facility on Fire Island in the Municipality of Anchorage. The three reports summarized here covered the three major phases of the study: (1) an assessment of future bed space needs of the Alaska Department of Corrections; (2) an evaluation of the physical site and cost estimates for prison construction and operation; and (3) a public opinion survey and open discussion.

Irish H & V News

Building Services Engineering

No abstract provided.

Agenda: Getting A Handle On Hazardous Waste Control, University Of Colorado Boulder. Natural Resources Law Center

Getting a Handle on Hazardous Waste Control (Summer Conference, June 9-10)

The conference chairman was University of Colorado School of Law professor Lawrence J. MacDonnell.

During the past ten years Congress has made the regulation of hazardous waste a priority. This conference focuses on the Resource Conservation and Recovery Act, as amended in 1984, and the Comprehensive Environmental Response, Compensation and Liability Act.

This conference attracted about 100 registrants from 16 states plus the District of Columbia. John G. Welles, Regional Director for EPA Region 8, presented a luncheon address.

Effects Of Load Distributions And Axle And Tire Configurations On Pavement Fatigue, Herbert F. Southgate, Robert C. Deen

Kentucky Transportation Center Research Report

Damage factor relationships for axle and tire configurations are presented. Adjustment factors are provided to account for variations in load distributions within axle groups, distances between axles of a tandem, and variations in tire pressure for both dual and flotation tires.

Properly accounting for accumulated fatigue of a pavement requires a traffic volume, proportions of vehicle styles (classifications) within the of service, estimate of the average damage factor for each classification, reasonable measure of traffic stream, dates and estimates of tire contact pressures.

All adjustment factors presented are based on analyses of a limited number of structures and should be …

Apparent Thermal Diffusivity Of Soil Determined By Analysis Of Diurnal Temperatures (Fourier Series, Nonlinear Regression)., Thomas Anthony Costello

LSU Historical Dissertations and Theses

A method of indirect measurement of the apparent thermal diffusivity of soil, in situ, was developed, tested, and evaluated. The method was based on an analysis of diurnal variations in soil temperature measured at several depths near the surface of an undisturbed mineral soil (a silty clay loam), near Baton Rouge, Louisiana. A thermocouple insertion technique was developed and implemented to precisely locate the sensors in undisturbed soil, thereby reducing experimental error in soil temperature measurement. The apparent thermal diffusivity was determined from an implicit relationship derived from transient one dimensional heat conduction theory. Nonlinear regression analysis was used to …

Analysis And Simulation Of The Pneumatic Braking System Of Freight Trains, Khaled Sayed Abdol-Hamid

Doctoral Dissertations

In North America, and in many other parts of the world, freight trains still employ pneumatic equipment for braking. The 26C locomotive valve and control valves of the cars are connected by a brake pipe which serves the dual purpose of conducting pneumatic power and transmitting the control signal (brake signal) from the locomotive to each car of the train. The development of the air brake system has been largely empirical and experimental, which may take years to develop a new design.

In this thesis, a new brake pipe mathematical model is developed, including the interaction of the branch pipe. …

Fire Resistance Of Concrete-Filled And Reinforced Concrete Columns, Mohamed El-Shayeb

Doctoral Dissertations

In order to calculate the fire resistance of a building component, it is necessary to know the temperature history of the component during exposure to fire. In this dissertation a numerical method is described for calculating the temperature field in fire-exposed columns. The procedure is based on a finite difference method for calculating the temperature history of concrete-filled square steel and cylindrical reinforced concrete columns. Two mathematical models and their related computer programs for these columns are presented in this dissertation.

Furthermore, the Division of Building Research of the National Research Council of Canada, is now carrying out extensive experimental …

Fate And Transport Of Low-Ph Hazardous Materials After Deep Well Disposal., Winton G. Aubert

LSU Historical Dissertations and Theses

The ultimate fate and chemical kinetics of low-pH hazardous wastes after deep well injection were studied. Two experimental approaches were taken. Chemical kinetics of reactions involving acids and typical formation clays was studied using a batch reaction scheme. The effects of reactions involving flowing acidic waste streams and disposal formations were characterized using sand packs of length one foot, four feet, and twenty feet. A numerical ground water flow simulator was used to model the interactions of flowing acidic wastes with linear sand packs and with a hypothetical waste disposal system. Reaction rate coefficients and activation energies were determined for …

Computer-Aided Analysis Of Formation Pressure Integrity Tests Used In Oil Well Drilling., Mauricio Aguiar Almeida

LSU Historical Dissertations and Theses

Formation pressure-integrity tests or leak-off tests have been increasingly performed throughout the world. The test is performed primarily to verify how much pressure can be applied to the formation below the bottom of casing, and to test the cement job sheath around the outside of the casing. The initial design of the various casing strings to be cemented in the well depends heavily on the predicted fracture-pressure curve. If this predicted curve is not verified by the test, the casing plan will have to be changed. Thus, verifying formation fracture-pressure during drilling is of great importance. However, the lack of …

Amine Removal From Aqueous Process Streams By Ligand Exchange., Wayne Bernard Bolden

LSU Historical Dissertations and Theses

Amines in aqueous, process feed or effluent streams can cause contamination problems. Ligand exchange demonstrates the potential to remove amines from these process streams. In ligand exchange, a complexing solute is removed from solution as it covalently bonds to a metal ion held on cation exchange resin. Previous work has shown copper(II)-carboxylic acid resin to be a suitable metal-resin exchange sorbent. The results of a research program are presented showing the applicability of ligand exchange to an amine removal operation. This study includes experimental determination of equilibrium relationships and diffusion coefficients. These parameters have been used to mathematically model ligand …

Olfactometric In Situ Soil Exploration: Development Of The Electro-Odo-Cone., Mohammad Mohammadi

LSU Historical Dissertations and Theses

The suitability of the electro-odo-cell (EOC) for detection of organic chemical contaminants in ambient air and soil strata was investigated under laboratory conditions. The existing concept of the EOC was modified to incorporate the system into a state of the art subsurface soil investigation probe (electric cone penetrometer). Partial theoretical support for EOC operation was developed. The state of the art in reactive solute transport in soils was reviewed. From this review inferences were made about time of travel of a permeant in soil samples, which was consequently compared with time of initial response of the laboratory prototype cone penetrometer …

Evaluation Of Some Properties Of Sugarcane Using Four Selected Techniques (Nmr, Nir)., Claudio Bianor Sverzut

LSU Historical Dissertations and Theses

A study was undertaken to evaluate new methods for rapid estimation of sugar, fiber, and moisture contents as well as the biomass of sugarcane. The NIR method can analyze the samples for sugar, moisture, fiber, and Pol values in less than one minute. The microwave method can reduce the time necessary to perform sugar and moisture analysis using the press method from 48 hours to a few minutes. Gamma ray transmission can be used to estimate crop yield in the field, and NMR can be used to measure the moisture content of whole stalks of sugarcane if its accuracy is …

Model Reduction Of Stochastic And Deterministic Continuous Time Linear Systems (Lypunov Equation, Schawrz Approximation)., Khier Benmahammed

LSU Historical Dissertations and Theses

Two new approaches for reducing the order of large scale continuous systems are presented. The first approach is a modified version of the aggregation technique. It uses the matching properties of the steady state output covariance and the Markov parameters of the high order system to those of the r('th) order model. This approach also uses a new algorithm derived for the computation of the controllability and observability Grammians, to produce controllable, observable and stable low order models. These is no unique method available for evaluating the aggregation matrix or the matrix relating the system state vector to the model …

Diligence Requirements Under The Federal Coal Leasing Amendments Act Of 1975, Gail L. Wurtzler

Public Lands Mineral Leasing: Issues and Directions (Summer Conference, June 10-11)

51 pages.

Contains references.

A Political Economy Study Of An Indigeneous Irrigation System., Nirmal Sengupta Dr.

Doctoral Theses

The present thesis is the study of a specifio indigenoous irrigation eystem following the general method of politioal coonomy. A couple of yeara baok when I had written for the firet time ubout this little-known but widespread irr igation aystem the artiole had driwn ocnaiderublo attention. The prosent study is a much detailed expooition of the sama syetem. The age old eystem of irrigaticn howover, 1e not mere ly a matter of historionl interest. It alao raisos many different quastione regarding developmant strategy and planning. I have devolop. the study so aia to be able finally, to deal with suoh …

Large Strain Theory As Applied To Penetration Mechanism In Soils (Plasticity)., Panagiotis Demetrios Kiousis

LSU Historical Dissertations and Theses

A theoretical analysis of a Quasistatic Cone Penetrometer Test (QCPT) is presented in this work. A large strain, elasto-plastic formulation is developed for this purpose and is implemented into a finite element method program. The basic relations of the theory are developed in an Eulerian reference frame, subsequently transformed to a Lagrangian coordinate system, and through simple time differentiation, the necessary rate equations are derived. Both isotropic and kinematic hardening of the Ziegler type are introduced in this theory. The plasticity models implemented are the extended von Mises and the cap model by DiMaggio and Sandler. The pore water pressures …

An Engineering Approach To Model-Order Reduction And Its Application To Controller Design., Alexius Ogbusua Kalu

LSU Historical Dissertations and Theses

A new method of approximating a high-order system by a lower-order model in the frequency domain is developed. A reduced-order model of a transfer function obtained by the new method is compared with a reduced-order model obtained by another existing method to illustrate the power of the technique. Furthermore the approximant constructed by this new method is used to design a control system, which is applicable to the plant, to show its usefulness. The thesis also suggests some mathematical criteria for selecting the order of the approximant. This technique is particularly attractive because of its simplicity and versatility. Furthermore, it …