Engineering Commons^™

A Receiving Water Quality Model For Dissolved Metal Runoff From A Floating Drydock, Thomas O. Fenn

Civil & Environmental Engineering Theses & Dissertations

A methodology for modeling the water quality mixing zone of dissolved metal bearing storm water runoff is presented with specific application to floating drydocks in a tidal estuary. The method relies upon a solution of the mass balance equation as contained in the computer program, Water Quality Analysis Simulation Program (WASPS), an Environmental Protection Agency (EPA) model. Separate applications are presented for dissolved metal and solid settling to optimize the WASPS program capabilities.

WASPS provides the capability to evaluate the mass balance equation in a finite difference scheme applied over a large number of small volume segments. The program may …

Sensitivity Analysis And Optimization Of Aerodynamic Configurations With Blend Surfaces, Almuttil Mathew Thomas

Mechanical & Aerospace Engineering Theses & Dissertations

A novel (geometrical) parametrization procedure using solutions to a suitably chosen fourth order partial differential equation is used to define a class of airplane configurations. Inclusive in this definition are surface grids, volume grids, and grid sensitivity. The general airplane configuration has wing, fuselage, vertical tail and horizontal tail. The design variables are incorporated into the boundary conditions, and the solution is expressed as a Fourier series. The fuselage has circular cross section, and the radius is an algebraic function of four design parameters and an independent computational variable. Volume grids are obtained through an application of the Control Point …

Gamma-Ray Optical Studies Of ⁷³Ge And ⁵⁷Fe, Walter Carlton Mcdermott Iii

Physics Theses & Dissertations

The research described herein is among the first attempts to test one of the more popular theories for development of a gamma-ray laser. This work is a "marriage" between the Borrmann effect, which is a consequence of the dynamical theory of x-ray diffraction, and time-filtering which comes from time-domain Mossbauer spectroscopy.

Our experiments involved the search for a nuclear Borrmann effect and the subsequent time-filtering effect using ⁵⁷Fe and ⁷³Ge. In both cases, no nuclear Borrmann effect was observed; however, the methodology and criteria necessary for such an observation with any isotope were documented. The procedures necessary for …

A Total Systems Analysis Method For The Conceptual Design Of Spacecraft: An Application To Remote Sensing Imager Systems, Knut I. Oxnevad

Engineering Management & Systems Engineering Theses & Dissertations

Increased emphasis is being placed on improving the performance of space projects, within tighter budgets and shorter development times. This has led to a need for more efficient space system design methods. The research described here represents an effort to develop and evaluate such a method.

Systems engineering and concurrent engineering together provide the theoretical foundation for the method. The method, derived from both this theoretical foundation and ideas from experts in the space industry, emphasizes a total systems analysis approach, taking into account given mission requirements, and the mathematical modeling of interactions between system variables and between subsystems. The …

Dynamic Lot Sizing And Scheduling In A Multi-Item Production System, Padmanabhan Soundar

Engineering Management & Systems Engineering Theses & Dissertations

In this research, algorithms are developed to address the problem of dynamic lot sizing and scheduling in a single level (or single operation) production system. This research deviates from previous research in this area in that it does not have the kind of assumptions regarding the real world production system that normally were made to reduce the complexity of the problem. Specifically, this research explicitly considers finite capacity, multiple items, known deterministic dynamic demand, sequence dependent setup times and setup costs, setup carryover and variable backlogging. The objective is to simultaneously determine the lot size and the sequence of production …

The Analysis, Simulation, And Implementation Of Control Strategies For A Pulsewidth Modulated Induction Motor Drive, Scott D. Roller, Chee Mun Ong

Department of Electrical and Computer Engineering Technical Reports

The purpose of this research is to analyze, simulate, and compare two different control strategies for a variable speed pulsewidth modulated induction motor drive, and implement one of the control strategies using the Motorola MC68F333 inicrocontroller. The two strategies examined in this technical report are volts per hertz control and field oriented control. The benefits and limitations of each strategy are examined through theoretical analysis. Verification of the analysis is performed by simulating thc strategies usmg the Simulink toolbox of Matlab. The Motorola microcontroller is then used to generate both edge-aligned and center-aligned pulsewidth modulated drive signals for a three …

Study Of Surface Heat Exchangers For High-Altitude Atmospheric Research Aircraft, Te-Kang Wang

Mechanical & Aerospace Engineering Theses & Dissertations

A flush-mounted heat exchanger concept, using the wing surface to dissipate heat, is investigated as a lower drag alternative to conventional ducted plate-fin radiators. A feasibility analysis is made for an unmanned high-altitude aircraft which will reach altitudes up to 25 kilometers. A computer code is used to calculate approximate heat transfer coefficients over the airfoil's surface. A model is tested in the Old Dominion University subsonic wind tunnel to verify the results of the computer code. The results indicate that a flush mounted heat exchanger design is able to provide 20 to 100 percent of the required heat dissipation …

The Progressive Failure Analysis Of Cut Slope In Anisotropic Strain Softening Soils, Jong Woon Choi

Civil & Environmental Engineering Theses & Dissertations

The failure phenomena in earth structures such as slopes and embankments on clay foundations are a consequence of the formation of failure surfaces.

A finite difference computer code, FLAC (Itasca Consulting Group, 1993), with the isotropic Mohr-Coulomb plasticity model, is used to analyze the undrained progressive failure of a strain softening soil during a slope excavation process. The focus of the study is on the short-term stability of slopes. In the first series of analyses, which are aimed at the evaluation of anisotropic strength effect on slope stability, the isotropic Mohr-Coulomb plasticity model is slightly modified to implement the anisotropic …

Status And Needs Assessment: Survey Of Irrigation Districts - Usbr Mid-Pacific Region, Charles M. Burt, Kris O'Connor, Stuart W. Styles, Mike Lehmkuhl, Chad Tienken, Robert Walker

BioResource and Agricultural Engineering

ITRC gathered data from 61 agricultural districts in the U.S. Department of the Interior Bureau of Reclamation's (USBR) Mid-Pacific Region by interviewing irrigation district personnel and studying their Water Conservation Plans. These districts comprise about 90% of the irrigated acreage in the Mid-Pacific Region. Data were analyzed to determine general demographic information, the degree of water delivery flexibility provided to farmers, and the extent of existing and planned district modernization.

A Study Of Kanban Based Production System In Cellular Manufacturing Environment, Sanjay Bhargava

Masters Theses

The study of effects of production data variabilities on Kanban based cellular manufacturing system is vital before its design and implementation because it would give better understanding of their uncertain behavior.

In this research, a detailed analysis of a Kanban system, with subcell scenario, under dynamic operating conditions is performed. The Control variables considered were number of Kanbans, processing time variability, demand variability and machine breakdown. The performance parameters considered were profit, production lead time, machine utilization and material processing lead time.

Approximately 200 simulation runs were made with 3 replications each by varying one control variable at a time. …

A Comparison Of Tool Life Of Two Coated Carbide Inserts Under Identical Conditions And At Different Cycle Times, Garold Zander

Graduate Research Papers

Coated hardmetals have brought tremendous increases in productivity since 1969, when they were first applied to cutting materials. These coatings are extremely hard and are very abrasion resistant. Typical coatings are alumina oxide, silicon nitride with metal oxides, titanium carbonnitrides with metal carbides, titanium nitride, titanium carbonitride, and zirconium oxide. This study examined two different coated cutting inserts to determine which would maximize performance for lathe operators.

The two chemical vapor deposition (CVD) coated indexible inserts examined were Carboloy CMNA 543 TP 100, and Carboloy CNMA 543 TP 10. Both cutting inserts were multi-coated with alumina (Al2O3 ), titanium nitride …

Developing Methods To Measure And Project Levels Of Combat Readiness In A Naval Aviation Squadron At The Unit Level, Michael Lawrence White

Engineering Management & Systems Engineering Theses & Dissertations

Among the various missions and levels in a military organization, the term "Combat Readiness" is defined in many ways. To a unit-level command, such as an aircraft squadron, it simply refers to the unit's capability to perform its assigned mission when called upon. The proof of that capability is evident in the aftermath of combat, however, it is too late at that point to address any shortcomings that may exist. The problem is, how can the unit effectively define, continuously measure, and confidently forecast its ability to perform in combat? A quantitative model based upon historical data that encompasses all …

Petrochemical Analysis By Remote Fiber-Optic Raman Spectroscopy And Partial Least Squares Regression Analysis, Philip Edmund Flecher Jr.

Chemistry & Biochemistry Theses & Dissertations

A dispersive Raman system with charge coupled device (CCD) detection, distributed Bragg reflector (DBR) diode laser excitation, and a fiber optic probe has been developed for the rapid analysis of petrochemicals and fuels. Initially, mock petroleum fuels with analyte concentrations from 1.S - 16% were prepared and analyzed with the system. The inability of the original index guided diode laser to maintain a constant frequency during the mock petroleum analysis was a recurrent problem. The DBR laser was subsequently shown to have stability superior to index guided lasers, and was used in the remainder of the research.

Real gasoline samples …

Wavelength Modulation Spectroscopy With Diode Lasers, Ying Lu

Electrical & Computer Engineering Theses & Dissertations

Wavelength Modulation Spectroscopy is a non-intrusive technique which enables several parameters such as concentration, velocity, and temperature of a target specie to be measured. The method involves a modulation of a probe laser beam and detection at the fundamental, or any harmonic frequency, by a phase-sensitive apparatus. The theory of wavelength modulation is discussed. Effects of the finite value of the wavelength modulation index, together with the effects of any residual amplitude modulation that often occurs simultaneously in a diode laser, are included. It is shown that there are several advantages in using detection harmonics orders greater than the second. …

Speech Feature Computation For Visual Speech Articulation Training, Stefan Auberg

Electrical & Computer Engineering Theses & Dissertations

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

Electron Beam Emission From A Ferroelectric Cathode, Crystal Briana Garland

Electrical & Computer Engineering Theses & Dissertations

The electron beam emission from a LTZ-2 (lead titanate-zirconate) ferroelectric cathode was characterized. The purpose was to determine the operation range for this type of electron emitter. The experimental apparatus consisted of a high voltage driving circuit with a charging voltage up to 30kV. A solid-state SCR switch is used to generate the high voltage pulse which induces a polarization change. Current densities on the order of 80A/cm² 30kV were achieved. The electron beam profile is Guassian. At long anode-cathode distances the measured current densities were found to be above Child-Langmuir space charge limits. The large current densities and …

Scheduling Processors For Distributed, Critical, Real-Time Systems, Hari K. Narasimhamurthy

Electrical & Computer Engineering Theses & Dissertations

The development of a procedure to obtain cyclo-static schedules for distributed, critical real-time applications is presented in this thesis. The applications considered in this thesis are characterized by hard deadlines and periodic inputs. The applica­ tions are described by a data flow graph model which guarantees performance. Given the data flow graph representation, processors are scheduled to complete tasks as specified in the representation. The scheduling technique separates the scheduling of tasks in time and the assignment of processors to tasks. While different criteria exist for task scheduling, a schedule which minimizes latency and maximizes throughput is used in this …

Improved Conversion Of Plant Oils And Animal Fats Into Biodiesel And Co-Product , Praveen R. Muniyappa, Scott C. Brammer, Hossein Noureddini

Papers in Biomaterials

Increased environmental awareness and depletion of resources are driving to develop alternative fuel from renewable resources that are environmentally more acceptable. Esters of fatty acids (bio-diesel, derived from the transesterification vegetable oils, have properties similar to components of peh-oleior~. based diesel fuel Cost has been a major factor slowing the commercializatio of bio-diesel! Glycerol is the coproduct of the esterification process. In this work the feasibility of the glyc-erol of vegetable oil. with crude glycerol derived from the transesterification of the vegetable oils and animal fats was studied. Utilization of the crude co-product of the biodiesel process was investi-gated for …

A Proposed Method Of Calibration And Correlation Of Weigh-In-Motion Systems, David L. Allen, Jerry G. Pigman

Kentucky Transportation Center Research Report

There are various types of weigh-in-motion systems currently in use by agencies that collect weight data. These include load cells, bending plate, capacitance pads, piezoelectric cables, and bridge WIM's. The response and behavior of these systems differs from one type to another. Most states calibrate these systems by one of two methods. The first is to calibrate by running a truck or trucks of known weights across the scales a number of times. The second is to use a sample of trucks from the traffic stream.

This report details a field calibration and correlation test site between a slow-speed WIM …

Unsteady, Transonic Flow Around Delta Wings Undergoing Coupled And Natural Modes Response: A Multidisciplinary Problem, Margaret Anne Menzies

Mechanical & Aerospace Engineering Theses & Dissertations

The unsteady, three-dimensional Navier-Stokes equations coupled with the Euler equations of rigid-body dynamics are sequentially solved to simulate and analyze the aerodynamic response of a high angle of attack delta wing undergoing oscillatory motion. The governing equations of fluid flow and dynamics of the multidisciplinary problem are solved using a time-accurate solution of the laminar, unsteady, compressible, full Navier-Stokes equations with the implicit, upwind, Roe flux-difference splitting, finite-volume scheme and a four-state Runge-Kutta scheme, respectively. The primary model under consideration consists of a 65° swept, sharp-edged, cropped delta wing of zero thickness at 20° angle of attack. In a freestream …

A One-Dimensional Model For Storm Breaching Of Barrier Islands, Cheol Shik Shin

Civil & Environmental Engineering Theses & Dissertations

A set of numerical models is developed for simulating the four stages of barrier breaching characterized by one horizontal spatial dimension.

The SBEACH model is employed for the first stage of dune/beach erosion. The Lax-Wendroff two-step explicit scheme for Stage II is developed to simulate initiation of ocean flood propagation on initially dry barrier islands and the method of characteristics (MOC), is employed to compute additional boundary data. The development of the Preissmann implicit scheme for water motion and a forward time centered space explicit scheme for sediment motion in Stages III and IV provide a tool to study the …

Study Of Periodic Gust Loads On Airfoils, Tatsuya Nakajima

Masters Theses

The wings on aircraft can experience unsteady loads due to atmospheric disturbances; e.g., wind, the wakes of other aircraft, structural vibrations, or some combination of these sources. In some cases flow unsteadiness can be beneficial by augmenting the lift and reducing the drag; under different circumstances temporal variations in the flow can induce stall or cause structural failure.

In this study, the response of isolated (and tandem) NACA 0012 airfoil(s) to time-periodic unsteadiness have been investigated. The sources of unsteadiness include a time-varying free stream flow angle, a time varying free stream velocity magnitude, and an oscillating airfoil.

The predicted …

Bs News

Building Services Engineering

No abstract provided.

Variational Methods In Sensitivity Analysis And Optimization For Aerodynamic Applications, Adem Ibrahim Hussen

Mechanical & Aerospace Engineering Theses & Dissertations

Variational methods (VM) sensitivity analysis, which is the continuous alternative to the discrete sensitivity analysis, is employed to derive the costate (adjoint) equations, the transversality conditions, and the functional sensitivity derivatives. In the derivation of the sensitivity equations, the variational methods use the generalized calculus of variations, in which the variable boundary is considered as the design function. The converged solution of the state equations together with the converged solution of the costate equations are integrated along the domain boundary to uniquely determine the functional sensitivity derivatives with respect to the design function.

The determination of the sensitivity derivatives of …

Pc Windows Finite Element Modeling Of Landfill Gas Flow, Stephen R. Mull, Robert L. Lang, Samuel A. Vigil, Harold M. Cota

Civil and Environmental Engineering

A two dimensional demonstration program, GAS, has been developed for the solution of landfill gas (LFG) flow problems on a personal computer (PC). The program combines a Windows™ graphical user interface, object oriented programming (OOP) techniques, and finite element modeling (FEM) to demonstrate the practicality of performing LFG flow modeling on the PC. GAS is demonstrated on a sample LFG problem consisting of a landfill, one gas extraction well, the landfill liner, cap, and surrounding soil. Analyses of the program results are performed for successively finer grid resolutions. Element flux imbalance, execution time, and required memory are characterized as a …

Ua3/8/5 Application For Cause Award For Excellence In Campus Networking, Wku President's Office-Meredith

WKU Administration Documents

Application for CAUSE award for excellence in campus networking gives details about the first WKU computer network.

Uncontrolled Air Flow In Non-Residential Buildings, Florida Solar Energy Center, James Cummings

FSEC Energy Research Center®

The objective of this study was to develop the capability to substantially reduce energy use, building degradation and indoor air pollution caused by uncontrolled air flow in nonresidential buildings. For purposes of the study, 'uncontrolled air flow' was defined as air moving across the building envelope or between zones or components of a building, where the pathways of flow, the direction of flow, and the origin of the air are unknown, unspecified, or unintended. The study comes to three major conclusions as follows: 1. Uncontrolled air flow is pervasive in buildings, often resulting in severe -- and sometimes even catastrophic …

Method And Apparatus For Destroying Organic Compounds In Fluid, Yin Zhang, John C. Crittenden, David W. Hand, David L. Perram

Michigan Tech Patents

An apparatus for the photocatalytic oxidation of organic contaminants in fluid includes a reactor and a photocatalyst affixed to support material. Preferably, the outer wall of the reactor is constructed of material transmissive of ultraviolet radiation. The support material preferably is transmissive of ultraviolet radiation. The support material can also be an adsorbent material. Also, a method for photocatalytic oxidation of organic contaminants in fluid. Also, a method for preparation of a supported photocatalyst. Also, a supported photocatalyst adapted for the photocatalytic oxidation of organic contaminants in fluid. Also, a method for preparing a photocatalyst adapted for the photocatalytic oxidation …

Comparison Of Function Approximation With Sigmoid And Radial Basis Function Networks, Gary Russell, Laurene V. Fausett

Electrical Engineering and Computer Science Faculty Publications

Theoretical and computational results have demonstrated that several types of neural networks have the universal approximation property, i.e., the ability to represent any continuous function to an arbitrary degree of accuracy, given enough hidden units. However, practical considerations, such as the relative advantages of different networks for function approximation using a small to moderate number of hidden units, are not as well understood. This paper presents preliminary results of investigations into the comparison of networks using sigmoidal activation functions and networks using radial basis functions. In particular, we consider the ability of several such networks to learn mappings from the …

Application Of Neural Networks To Channel Assignment For Cellular Cdma Networks With Multiple Services And Mobile Base Stations, William S. Hortos

Electrical Engineering and Computer Science Faculty Publications

The use of artificial neural networks to the channel assignment problem for cellular code- division multiple access (CDMA) telecommunications systems is considered. CDMA takes advantage of voice activity and spatial isolation because its capacity is only interference limited, unlike time-division multiple access (TDMA) and frequency-division multiple access (FDMA) where capacities are bandwidth limited. Any reduction in interference in CDMA translates linearly into increased capacity. FDMA and TDMA use a frequency reuse pattern as a method to increase capacity, while CDMA reuses the same frequency for all cells and gains a reuse efficiency by means of orthogonal codes. The latter method …