Engineering Commons^™

Optimizing Irrigation Management For Pollution Control And Sustainable Crop Yield, Ghassan R. Musharrafieh, Richard C. Peralta, Lynn M. Dudley, Ronald J. Hanks

Civil and Environmental Engineering Faculty Publications

Irrigation strategies which maximize crop yield while preventing salt from leaching to the groundwater or undesirable salt increases in the root zone are computed by using a one-dimensional simulation/optimization management model. The included constraint equations maintain a water volume balance and salt transport in the unsaturated zone. Implicit finite difference forms of the unsaturated water flow equation (Richards' equation), the diffusion-convection solute transport equation, functions describing the hydraulic properties of the medium, a root extraction function, and other constraints are used. The model uses a large discretization in time. A cyclic prediction and correction type of approach is adopted to …

Maximizing Tce Removal From A Contaminated Aquifer, Richard C. Peralta, Alaa H. Aly

Civil and Environmental Engineering Faculty Publications

A methodology for developing pumping strategies to maximize contaminant extraction is presented. The methodology consists of approximating the mass removal integral using a quadrature rule. Contaminant mass extraction is expressed as a function of the extraction rates. The relation of contaminant extraction to pumping rates is used as one of several constraints within a simulation/optimization model. The implementation and application of the methodology are described. The result is a set of pumping rates which are optimal in the sense that they maximize the mass of contaminant removed by the extraction system for a posed management scenario.

Us/Remax (Vs 2.70): Software For Optimizing Management Of Stream/Aquifer Systems Using The Response Matrix And Related Methods, Richard C. Peralta, Alaa H. Aly

Civil and Environmental Engineering Faculty Publications

US/REMAX is designed to assist water managers in developing optimal groundwater and/or surface water strategies for a wide range of management problems. US/REMAX uses the response matrix method, which assumes that physical system response to stimuli is linear. However, US/REMAX can also address nonlinear systems via cycling. In one application, a strategy computed using US/REMAX required 40% less pumping than one obtained via a normal simulation model. US/REMAX also easily computes tradeoffs for multiobjective problems.

Predicting Utility Bills For Air Combat Command A Study Of Forecasting Techniques, William L. Luthie

Engineering Management & Systems Engineering Theses & Dissertations

Many companies use forecasting techniques as a tool in managing their assets. Trends in such items as sales, population and inventory levels have all been determined at one time or another using forecasting, yet research indicates that these tools have not been utilized to predict utility budgets. This research was conducted to determine if such techniques could be applied to the specific task of predicting the utility bill at an Air Force base. Three quantitative models were chosen, the Moving Average, Exponential Smoothing and Regression, to determine their applicability to the task at hand. One base within Air Combat Command, …

Extension To The Dynamic Modeling Of The Large Angle Magnetic Suspension Test Fixture, Lucas E. Foster

Mechanical & Aerospace Engineering Theses & Dissertations

The Large Angle Magnetic Suspension Test Fixture (LAMSTF) is a laboratory scale proof-of-concept system. The configuration is unique in that the electromagnets are mounted in a circular planar array. A mathematical model of the system had previously been developed, but was shown to have inaccuracies. These inaccuracies showed up in the step responses. Eddy currents were found to be the major cause of the modeling errors. In the original system, eddy currents existed in the aluminum baseplate, iron cores, and the sensor support frame. An attempt to include the eddy current dynamics in the system model is presented. The dynamics …

Automatic Differentiation For First- And Second-Order Sensitivity Derivatives Of A Cfd Code, Laura Lee Sherman

Mechanical & Aerospace Engineering Theses & Dissertations

The straightforward automatic-differentiation and the hand-differentiated incremental iterative methods are interwoven to produce a hybrid scheme that captures some of the strengths of each strategy. With this compromise, discrete aerodynamic sensitivity derivatives are calculated with the efficient incremental iterative solution algorithm of the original flow code. Moreover, the principal advantage of automatic differentiation is retained (i.e., all complicated source code for the derivative calculations is constructed quickly with accuracy). The basic equations for second-order sensitivity derivatives are presented; four methods are compared. Each scheme requires that large systems are solved first for the first-order derivatives and, in all but one …

Roadway Related Tort Liability And Risk Management: 3rd Edition, Daniel S. Turner, Kenneth R. Agent

Kentucky Transportation Center Research Report

This training material has been prepared to address the tort liability problems faced by the Kentucky Transportation Cabinet and Kentucky local governments. The workbook defines the problem by reviewing the national picture of growing numbers of suits and escalating financial losses from suits against highway agencies.

The workbook also sets out solutions, and reviews actions which can decrease the exposure of highway agencies to these suits. This risk management concept is emphasized throughout the workbook.

Fetal Heart Rate Detection With A Passive Acoustic Sensor System, Zongyao Zhou

Electrical & Computer Engineering Theses & Dissertations

Research and development is presented of real time signal processing methodologies for the detection of fetal heart tones from noise contaminated signals obtained from passive acoustic sensors. A nonlinear Teager energy operator is utilized for detection of the fetal heart tone event. Autocorrelation and a parallel redundancy correction algorithm derives fetal heart rates. A real time monitoring system is described which records and plots the time history of both the fetal heart rate and the acoustic fetal heart signal. The system is validated in the context of the fetal nonstress test. Comparisons are made with ultrasonic nonstress tests on a …

Open-Loop State-Space Model Identification From Closed-Loop Data, Lori Guy

Mechanical & Aerospace Engineering Theses & Dissertations

This thesis provides an investigation of a system identification algorithm which identifies an open-loop state-space model from a linear system that is operating under closed-loop conditions. In order to investigate the system identification algorithm some basic ideas of system identification theory are reviewed. Examples using simulated data are presented to characterize the effects of varying the parameters for open-loop and closed-loop system identification processes. Both noise· free and noise contaminated cases are simulated. Linear Quadratic Gaussian (LQG) control theory is reviewed and the motivation for using iterative LQG control feedback is discussed. The derivation of the proposed system identification algorithm …

An Investigation Of Hole Size Effects In A Composite Material During Tensile Fracture, David Floyd Moore

Mechanical & Aerospace Engineering Theses & Dissertations

An experimental investigation was conducted to evaluate the hole size effects, i.e., the reduction in strength with an increase in hole size at a constant stress concentration factor, for a glass fiber reinforced epoxy crossply laminate during tensile fracture. The characteristic dimension according to the point-stress and average-stress criteria of the two-parameter models proposed by Whitney and Nuismer were determined and compared for a circular hole, optimized circular hole, square hole with radiused corners and square hole with sharp corners. Modified versions of the two-parameter models proposed by Karlak and Pipes, Wetherhold, and Gillespie were also compared. On the basis …

Component Mode Synthesis-Based Design Methodology For Structural Modification And Synthesis, Venkateshwarlu Maroju

Mechanical & Aerospace Engineering Theses & Dissertations

In this work, structural modification and synthesis techniques based on component mode synthesis are presented. The component mode synthesis method formulates the eigenvalue equation of an entire structure in terms of the vibration characteristics of individual components in the assembly. Through this functional relationship, the individual components are successfully treated as the design entities in the proposed methodology. Unlike conventional design modification techniques that can only treat the properties of the finite elements as the design variables, this technique uses the vibration and static responses of the individual components as the design entities. The sensitivity derivatives of the global responses …

Understanding Collaborative Writing Of Technical Proposals With A Process/Product Model, Frank Joseph Greco

Engineering Management & Systems Engineering Theses & Dissertations

Group work creates concerns with respect to performance, collaboration, and conflict management. Writing technical proposals creates appropriate settings for gaining insight into work group efficiencies and project conflict. The research involved different work groups preparing responses to Federal Government solicitations. A proposed Process/Product model was applied to create a new framework and perception of the technical proposal development effort. There exists a rich dialectic between the forces of Process, (how the effort is accomplished), and, Product, (what the effort will produce.) The investigation attempted to learn if the P/P model provides explanations for project conflict during technical collaborative writing.

The …

Bs News

Building Services Engineering

No abstract provided.

Development Of A Knowledge-Based System For Generating Process Plans Using Group Technology: A Study For Norfolk Naval Shipyard, William P. Keene Jr.

Engineering Management & Systems Engineering Theses & Dissertations

The purpose of this research was to study and analyze the Norfolk Naval Shipyard's manufacturing methods of determining part families and generating part process plans for parts in the machine shop. A knowledge-based decision support system was designed based on knowledge acquired from machinist experts and documented sources of the Norfolk Naval Shipyard. The system interprets specific part information provided by the user, categorizes parts into part families and generates process plans to manufacture the parts. The system was evaluated and tested for parts provided by Norfolk Naval Shipyard.

Hardware/Software Codesign And Simulation With The Occam Programming Language, Roy L. Krans

Masters Theses

Hardware/software codesign is an increasingly popular method for improving system performance and adaptability while minimizing cost. The goal of this design approach is to achieve the desired system characteristics (performance, fault tolerance, cost, power consumption, etc.) by carefully distributing the system functions among hardware and software components. Popular tools for describing this dual hardware/software functionality are behavioral languages such as C++ and Ada. These languages typically include facilities for both traditional sequential programming as well as behavioral modeling.

This thesis examines the effectiveness of occam as a behavioral language and its role in hardware/software codesign. The occam language is used …

Finite Element Nonlinear Random Response Of Composite Panels Of Arbitrary Shape To Acoustic And Thermal Loads Applied Simultaneously, Roger R. Chen

Mechanical & Aerospace Engineering Theses & Dissertations

The nonlinear random response of composite plates to the simultaneously applied, combined acoustic/thermal loads are investigated in this dissertation. A finite element formulation for the nonlinear random response is developed. The three-node Mindlin plate element with improved transverse shear is extended and employed. The extension includes the development of the thermal geometric matrix, the mass matrix, the first- order and second-order nonlinear stiffness matrices, and the thermal and mechanical load vectors. An innovative solution procedure has been created which is believed to be the first attempt to analyze nonlinear random response of complex composite panels subjected to simultaneous acoustic and …

Identification And Characterization Of The Iron-Zinc Intermetallics Formed In Galvanneal Steel, Richard Frederick George Grant

Physics Theses & Dissertations

The demand to improve the corrosion resistance of steel sheet, particularly for use within the automotive industry, has led to a dramatic increase in the use of coated steels in place of cold-rolled sheet steel. Galvanneal steel results from the post annealing of the zinc-coated steel sheet, in which iron and zinc are interdiffused to form an iron-zinc alloy coating. Within this alloy coating, four main iron-zinc phases, Zeta, Delta, Gamma-1, and Gamma may be present. Manufacture of the most suitable coating requires identifying which phases form during the galvannealing process, an understanding of the properties of each phase and …

An Investigation Of The Speed And Power Limitations Of A Copper-Doped Gallium Arsenide Photoconductive Switch, David Clifton Stoudt

Electrical & Computer Engineering Theses & Dissertations

The processes of persistent photoconductivity followed by photo-quenching are demonstrated in copper-compensated, silicon-doped, semi-insulating gallium arsenide. These processes allow a switch to be developed that can be closed by the application of one laser pulse (λ = 1.06 μm) and opened by the application of a second laser pulse with a wavelength equal to twice that of the first laser (λ= 2.13 μm). Switch closure is primarily achieved by elevating electrons from a deep copper center which has been diffused into the material. The opening phase is a two-step process which relies initially on the absorption of the 2-μm laser …

Novel Kalman Filtering Method For The Suppression Of Gyroscope Noise Effects In Pointing And Tracking Systems, Marcelo C. Aigrain

Department of Electrical and Computer Engineering: Faculty Publications

A primary cause of degraded performance in pointing and tracking systems is the jitter in the line of sight. This jitter is caused by the residual angular motion of the stabilized platform within the system. A major contributor to this residual motion is the gyroscope noise. Thus, to reduce angular jitter, lower-noise gyroscopes are selected, generally at a premium cost. Another approach is to enhance the accuracy of the gyroscopes electronically (by suppressing measurement noise) before their outputs are fed into the stabilized platform control system. Optimal filtering techniques can be used for this purpose. The goal is to estimate …

Tractor Test Museum Committee Meeting March 17th, 1995, Tractor Museum

Lester F. Larsen Tractor Museum: Planning and Development Documents

Camp Creek Threshers Foundation Funds 1915 Ford tractor restoration

Automatic Synthesis Of Vlsi Layout For Analog Continuous-Time Filters, David Lyle Robinson

Dissertations and Theses

Automatic synthesis of digital VLSI layout has been available for many years. It has become a necessary part of the design industry as the window of time from conception to production shrinks with ever increasing competition. However, automatic synthesis of analog VLSI layout remains rare.

With digital circuits, there is often room for signal drift. In a digital circuit, a signal can drift within a range before hitting the threshold which triggers a change in logic state. The effect of parasitic capacitances for the most part, hinders the timing margins of the signal, but not its functionality. The logic functionality …

Fiber Optic Detector And Depth Sensor And Method For Doing Same, Lawrence W. Evers, Kenneth J. Jackson

Michigan Tech Patents

A fiber optic sensor for determining the presence and/or measuring the depth of a first substance capable of transmitting light. The fiber optic sensor includes a plurality of light receiving fibers, a plurality of light transmitting fibers surrounding the light receiving fibers and structure for refracting light from the light transmitting fibers at a predetermined angle for total internal reflection of the light from an interface of the first substance with a second substance.

Acuta Enews March 1995, Vol. 24, No. 3

ACUTA Newsletters

In This Issue

Board report

President's message

ACUTA hires Administrative

DC at a glance

Info Superhighway grant

From ACUTA Headquarters

Analysis Of Support Conditions Under Joined Concrete Slabs Along Ush 18/151, James Crovetti

Transportation Reports with the Wisconsin Department of Transportation

The Wisconsin Department of Transportation has been constructing jointed concrete pavements incorporating open graded permeable base (OGPB) layers for a number of years. The OGPB layer has been constructed using non-stabilized, asphalt stabilized, and cement stabilized aggregates of varying gradations. Test sections have been established throughout the State of Wisconsin and have been monitored for performance for the last 5 years. To date, little if any performance variations after limited trafficking have been noted for jointed PCC sections constructed over OGPB layers as compared to those constructed over conventional dense graded aggregate base layers.

Data was collected along USH 18/151 …

A Discrete Single Server Queue With Markovian Arrivals And Phase Type Group Services, Attahiru Sule Alfa, K. Laurie Dolhun, Srinivas R. Chakravarthy

Industrial & Manufacturing Engineering Publications

We consider a single-server discrete queueing system in which arrivals occur according to a Markovian arrival process. Service is provided in groups of size no more than M customers. The service times are assumed to follow a discrete phase type distribution, whose representation may depend on the group size. Under a probabilistic service rule, which depends on the number of customers waiting in the queue, this system is studied as a Markov process. This type of queueing system is encountered in the operations of an automatic storage retrieval system. The steady-state probability vector is shown to be of (modified) matrix-geometric …

Reaction Fronts In A Porous Medium. Approximation Techniques Versus Numerical Solution, Fernando Escobedo, Hendrik J. Viljoen

Papers in Reaction Kinetics

The flame sheet approximation (FS) and a novel polynomial approximation technique (PA) are compared in terms of their capability to describe reaction fronts of highly exothermic reactions in a porous medium. A one-phase model and a two-phase model of a system with adiabatic walls and a radiant output (to approximate the case of a porous radiant burner) are included in the analysis. By matching the reaction zone solution found by either the FS or PA method with the solutions of the nonreacting zones, the temperature, conversion, and position of the reaction zone were determined. Numerical solutions for catalytic and noncatalytic …

Flight-Deck Automation: The Attitudes And Perceptions Of Selected Boeing 757/767 Air Carrier Pilots, William Woodrow Clark

Master's Theses - Daytona Beach

Development in electronic displays and computers have enabled avionics designers to present the pilot with ever increasing amounts of information in greater detail and with more accuracy- However, technological developments have not always brought about enhancement of the pilot's role. Investigating the interaction of cockpit crew members and the vast array of automated systems they control and monitor will contribute to the determination the effect this interface has on the performance of the cockpit team. This study utilized a questionnaire to determine if the opinions of the flight crew suggested performance is impacted negatively by automation. There was no significant …

Proceedings Of The 1995 Annual Symposium On Engineering Geology And Geotechnical Engineering (No. 31), Joseph A. Caliendo

Reports

No abstract provided.

Apparatus For Rotational Motion, Said Shakerin

All Faculty Articles - School of Engineering and Computer Science

No abstract provided.

Wiping Out Tall Weeds, Brad Rayner

Journal of the Department of Agriculture, Western Australia, Series 4

Control of weeds is an on-going battle for farmers, with many weapons becoming increasingly expensive. A refreshing exception to this trend is the blanket wiper, a cheap but effective meens of applying herbicides to taller weeds in pasture. Brad Rayner explains how it works.