Physical Sciences and Mathematics Commons^™

Collisional Dynamics Of The B3Π(O+) State Of Bromine Of Monofluoride, David W. Melton

Theses and Dissertations

When Bromine is combined with flourine atoms and discharged oxygen in a flow tube is produced in a highly non thermal distribution peaking at v'=3. The emission was linearly dependent on the concentration. The observed dependence of the BrF(B) emission on Bromine and atomic oxygen is inconsistent with a steady state prediction of a sequential excitation mechanism, where BrF(X) is excited by successive collisions with singlet oxygen. The experimental data are consistent with a three body mechanism involving Br and F atoms. Electronic quenching of BrF(B) by a number of collision partners (Br₂, CO₂, O_{2 …}

An Ada Based Expert System For The Ada Version Of Satool Ii, Min-Fuh Shyong

Theses and Dissertations

This thesis continues the work of implementing the expert system for the Ada version of SAtool II, an software design requirement analysis tool. The background, history, design process together with the design results and validation of the implementation with Ada and CLIPS/Ada is presented.

Quenching And Rotational Energy Transfer In Molecular Bromine: Br2(B), Dean A. Massman

Theses and Dissertations

This study investigates the rotational energy transfer processes of optically excited bromine molecules in the presence of several collision partners. Resolved laser induced fluorescence spectra of collisionally populated rotational states were analyzed by means of Stern Volmer analysis. Total rotational removal rate coefficients and state-to-state rotational removal rate coefficients for the v'=11,J'=35 level of Br₂(B) were obtained for collisions with Br₂(X), He, Ar and Xe. Rotational removal rate coefficients were also obtained for the v'11, J'=26 and 47; v'=14, J'=36 states of Br₂(B) with collisions with Ar. Total rotational removal rate for Br_{2 …}

The Boundary Element Method Applied To The Two Dimensional Stefan Moving Boundary Problem, Donald C. Vosika

Theses and Dissertations

This thesis considers problems for which the boundary is not known before the problem is solved and must be determined as part of the solution. We consider a time dependent problem which results in a moving boundary. We look at the heat conduction/diffusion equation in one and two spatial dimensions. We use Green's Theorem to yield a Volterra boundary integral equation which involves an unknown function on the moving boundary. We use the boundary element method to obtain a solution. Graphical results for the two dimensional problem are presented.

Transfer Of 4gl Application From Ingres To Oracle, Adnan Altunisik

Theses and Dissertations

This paper documents the transfer of 4GL applications from INGRES to ORACLE. As a result of a fast and conceptual change in computer languages, 4GLs were developed and evolved. These are programming support tools whose goal is, basically, to make the programs more efficient by reducing the number of instructions. Both ORACLE and INGRES database systems use 4GLs to develop applications. Their 4GL environments and their facilities for application development are investigated and explained in depth in this effort. The TWX application, which was originally implemented in INGRES by using its 4GL, is designed and reimplemented in ORACLE. This is …

Optimal Iterative Task Scheduling For Parallel Simulations, Joann M. Sartor

Theses and Dissertations

The ultimate purpose of this research is to reduce the time needed for execution of parallel computer simulations. In particular, the impact of task assignment strategies is determined for parallel VHDL circuit simulations. The classical scheduling problem, which assigns n precedence-constrained tasks to m processors is NP-complete in all but the simplest cases. The problem of assigning simulation tasks is further complicated by the iterative nature of computer simulations: each task is required to execute multiple times as the simulation executes. This investigation develops a polynomial-time algorithm (the level strategy) which provides optimal assignment for iterative systems with specific constraints. …

A Computer Simulation Of Braitenberg Vehicles, Eric B. Werkowitz

Theses and Dissertations

In his treatise, Vehicles: Experiments in Synthetic Psychology, Valentino Braitenberg used simple, autonomous vehicle designs to illustrate the principles behind animal nervous system organization and operation. The goal of this effort was to produce a computer program to allow a researcher to experiment with these concepts and to analyze their performance using methods employed by experimental psychologists. The resulting program allows the user to design vehicles that respond to changes in their environments and that have the ability to adapt their behavior, using a learning algorithm developed by Teuvo Kohonen. The vehicle designer is free to select sensor attributes, …

A Study Of The Liquid-Solid Interface During Rapid Resolidification Of Cooper-Titanium Using Molecular Dynamics, Craig L. Loisel

Theses and Dissertations

The behavior of the liquid-solid interface during resolidification of a condensed copper-titanium crystal is studied by atomistic simulation. A system of 1080 atoms (540 of each type) was simulated. The interface was created using monte carlo techniques and resolidification was performed by molecular dynamics. Resolidification was attempted at temperatures of 1200 K, 1100 K, 1000 K, 900 K, 818 K and 773 K. The liquid-solid interface was found to move only at 773 K, resulting in a chemically disordered crystal. The interface velocity observed in the simulation is 6.6 m/s which agrees well with the theoretical value of 5.5 m/ …

Calculated Point Defect Properties Of The Intermetallic Compounds Nickel Titanium (Niti) And Iron Titanium (Feti), Russell T. Lutton

Theses and Dissertations

Atomistic simulation with a modified version of the DYNAMO code was used to calculate the point defect properties of the intermetallic compounds nickel titanium and iron titanium. The calculated energies are believed to be experimentally accurate to within ± 0.1 eV. Vacant Ni or Fe lattice sites were preferred and had energies of 6.356 eV for NiTi and 5.899 eV for FeTi. Removing a Ti atom resulted in a neighboring antisite defect caused by migration of a Ni or Fe atom into the vacant Ti site. These configurations had energies of 7.024 eV for NiTi and 6.336 eV for FeTi. …

High Altitude Neutral Particle Transport Using The Monte Carlo Simulation Code Mcnp With Variable Density Atmosphere, David L. Monti

Theses and Dissertations

The Monte Carlo transport code, MCNP was modified for purposes of two dimensional neutron-photon transport modelling in a variable density atmosphere. Calculations were performed using cylindrical (r, z) geometry and a point isotropic neutron-photon source at an elevation of 40 kilometers. Neutron and photon fluence results were computed using ring detectors for field points at constant range versus source elevation angle and for field points at constant altitude versus radius. Comparisons between the modified and unmodified versions of MCNP showed a decrease in run time by a factor of two was possible. Only a fraction of the spatial cells previously …

Mapping Efficient Numerical Methods To The Solution Of Multiple Objective Linear Programs, Michael A. Shields

Theses and Dissertations

This investigation was initiated to increase the speed, accuracy and capacity of m-simplex algorithms for solving multiple objective linear programming problems. Specifically, improvements were sought through the application of general numerical techniques. It soon became apparent that the m- simplex algorithm, like the simplex algorithm, is heavily dependent upon the technology of solving related systems of linear equations. The numerical arguments for the application of LU triangular matrix factorization techniques to simplex computations are well known. OF special significance to m-simplex performance is the case of rank-k updates to basis factorizations. A stable and efficient LU approach to the rank-k …

New Modified Anderson-Darling And Cramer-Von Mises Goodness-Of-Fit Tests For A Normal Distribution With Specified Parameters, Goksel Kahya

Theses and Dissertations

This thesis improves the powers of the Anderson-Darling and Cramer-von Mises goodness-of-fit tests using the mean rank and the median rank plotting positions. A Monte Carlo simulation of 5000 repetitions is used to generate the critical values from n =4 through n =80 for certain significance levels. An extensive power study is performed to compare the powers of the modified tests to the known tests for the uniform, the exponential, the double exponential, the lognormal, and the Weibull distributions. The power of the A-D tests modified by the median rank plotting and the mean rank plotting position are approximately 0.01% …

A Goodness-Of-Fit Test For A Family Of Two Parameter Weibulls With Known Shape Using Minimum Distance Estimation Of Parameters, John S. Crown

Theses and Dissertations

This research is to produce a modified Anderson-Darling goodness of fit test for the Weibull distribution when the location parameter is found by minimum distance estimation, the shape parameter is assumed known, and the MLE is used for the scale parameter. The critical values for the Anderson-Darling test are generated via Monte Carlo simulation when both the Anderson-Darling and Cramer-Von Mises distance statistics are minimized. These critical values are then used for a power study. The Monte Carlo simulation used 5000 repetitions for sample sizes of 5,8,12,15,16,20 and 25 with the Weibull shape parameter of . 5(.5)4.0. The power study …

A Network Flow And Goal Programming Approach To Modeling The Impact Of Pre-Accession Training To The Trained Personnel Requirements Process, William J. Beveridge

Theses and Dissertations

HQ ATC was tasked to analyze the impact of pre-accession training to the Trained Personnel Required (TPR) and training production process. Pre- accession training is a policy of providing contracted initial skills training to enlistees prior to entering basic military training. The purpose of this study was to develop a method to model the impact of pre-accession training. A network modeling and goal programming approach was used. Comparisons between the current training policy and a pre-accession training policy were made. Sensitivity was conducted on the impact of a balk rate on the new policy. The balk rate is the percent …

An Assessment Of The Accuracy Of Semi-Empirical Quantum Chemistry Calculations Of The Mechanical Properties Of Polymers, James R. Shoemaker

Theses and Dissertations

The ultimate mechanical properties of polymers, assuming perfect morphology, will be limited by the mechanical properties of a single, ideal polymer chain. Previous calculations of polymer chain moduli using semi- empirical (SE) quantum chemistry methods have resulted in modulus values much higher than experimentally measured. This study investigated the error in the calculated inherent to the method of calculation by comparing SE results for C-C bond potentials in two well characterized polymers, polyethylene and polydiacetylene. It was found that the SE calculation systematically overpredicted bond stiffness in these polymers by approximately 25% to 30%. This is the upper limit on …

An Automated Red Player For The Theater Warfare Exercise, Karl W. Kabanek

Theses and Dissertations

The Theater Warfare Exercise (TWX) is a two-sided, theater-level, decision-making exercise created, maintained and used by the personnel at the Air Force Wargaming Center. It is used to allow military officers to practice the decision-making process needed for the wartime employment of air power. An automated player was designed and a prototype implemented for the red (enemy) player using an expert system shell. The automated red player uses the TWX database that contains the data on the different units used in exercise. From the data the automated red player builds mission packages for the various types of missions required in …

Classification Of Newborns Based On Maturity Rating And Intrauterine Growth At The Medical College Of Virginia Hospitals, Lydia Holmes Sund

Theses and Dissertations

Nurses at the Medical College of Virginia Hospitals (MCVH) in Richmond, Virginia, use the Newborn Maturity Rating and Classification Tool to identify high risk infants. An estimate of gestational age is made and using this estimate, weight, length, and head circumference measurements are plotted on graphs on the tool to determine if the infant achieves intrauterine growth smaller, larger or equal to gestational age.

The data used to generate the graphs on the Newborn Maturity Rating and Classification Tool were collected in Colorado during the 1950's. Two nurses at MCVH questioned the use of these graphs. They wanted to know …

The Problem Of Mutual Exclusion: A New Distributed Solution, Rajeev Chawla

Theses and Dissertations

In both centralized and distributed systems, processes cooperate and compete with each other to access the system resources. Some of these resources must be used exclusively. It is then required that only one process access the shared resource at a given time. This is referred to as the problem of mutual exclusion. Several synchronization mechanisms have been proposed to solve this problem. In this thesis, an effort has been made to compile most of the existing mutual exclusion solutions for both shared memory and message-passing based systems. A new distributed algorithm, which uses a dynamic information structure, is presented to …

A Detailed Gravity Study Over A Known Devonian Carbonate Buildup: The Shell Golden Reef, Northwestern North Dakota, Stephen M. Braun

Theses and Dissertations

A detailed gravity study was conducted over the Shell Golden reef in the northwestern North Dakota portion of the Williston Basin. The Shell Golden reef has been previously interpreted to be reefal facies within the Winnipegosis Formation (Devonian) located at a depth of about 2400 meters. Based only on information from wireline logs and core from two boreholes, the Shell Golden well #34X-34 has been previously interpreted as a pinnacle reef with 70 meters of relief and undetermined diameter. The basin regime of the Elk Point shelf created an environment that allowed the growth and development of the Shell Golden …

Tectonic History Of Billings And Southern Mckenzie Counties, Southwestern North Dakota, John J. Crashell

Theses and Dissertations

Billings and southern McKenzie Counties contain about 40 active oil and gas fields. In the same area, two major structural highs and several minor ones can be recognized. The first of these, the Billings anticline, extends approximately 60 km (18 mi.) along a north-south line in central Billings County, and is composed of two parallel folds. A second major structure, here termed the Rough Rider anticline, lies west of the Billings anticline, and also extends about 60 km (18 mi.) along a north-south line from north-central Billings County into southern McKenzie County. Both of these structures are fault-bounded on their …

Erosion Of Fractured Banks, Lake Sakakawea, Western North Dakota, Mark C. Elliott

Theses and Dissertations

Shoreline erosion at Lake Sakakawea has exceeded originally predicted rates. This thesis is a continuation of a project, begun in 1983, to study erosion rates, causes, and prediction; the purpose has been to describe variations in fracture patterns in shoreline banks and assess their affects on erosion rates.

During the first phase of this project (1983-1986), average bank recession was rapid (l.Sm/yr) and factors related to wave action, including fetch, bank orientation, and beach composition, were most important. Since 1986, low lake levels have persisted and wave action has not been a factor; however banks continue to recede, but at …

Fracture-Enhanced Porosity And Permeability Trends In The Bakken Formation, Williston Basin, Western North Dakota, Wayne B. Freisatz

Theses and Dissertations

Fractures play a critical role in oil production from the Bakken Formation (Devonian and Mississippian) in the North Dakota portion of the Williston Basin. The Bakken Formation in the study area is known for its low matrix porosity and permeability, high organic content, thermal maturity, and relative lateral homogeneity. Core analysis has shown the effective porosity and permeability development within the Bakken Formation to be primarily related to fracturing.

In theory, lineaments mapped on the surface reflect the geometry of basement blocks and the zones of fracturing propagated upward from them. Fracturing in the Williston Basin is thought to have …

Three Degrees Of Freedom Compliant Motion Control For Robotic Aircraft Refueling, Clayton M. Andersen

Theses and Dissertations

The Air Force Institute of Technology (AFIT) supports on-going research in application of robotic technology to enhance assembly tasks. As a testbed, AFIT supports the ground-based aerial refueling project, with an emphasis on visual servoing techniques and compliant motion control. This thesis focuses on compliant motion control. Previous research developed the testing environment, which includes a PUMA-560 industrial manipulator, and a half scale mock-up of an aerial refueling system. This effort corrected and expanded the existing two degree of freedom (DOF) compliant controller to three DOF. Three DOF compliance was demonstrated by inserting the refueling nozzle into the receiver port. …

Realistic Orbits About The Martian Moons, Samuel R. Bryant

Theses and Dissertations

Orbits about the Martian moons, Phobos and Deimos, previously found to be stable by the Poincare surface of section technique in a restricted three- body system, were investigated with non-zero eccentricity of the moons added to the dynamics of the planar four-body system (Mars, moon sun, artificial satellite). Although not strictly applicable to this case, the surface of section technique was used to verify whether or not the previously found stable orbits were realistic when a real world perturbation was added to the system dynamics. The surface of section technique involves the numerical integration of several orbits with the same …

Use Of Grasp Force Focus Positioning To Enhance The Torque Resistance Capability Of Robotic Grasps, Stephen G. Edwards

Theses and Dissertations

Three-point-contact grasps are unique in that the homogeneous solution for the contact forces always produces a grasp force focus. Careful positioning of this focus point in the grasp plane can help avoid two things; slipping at the contact points, and violation of joint torque limits. The focus placement method is explored theoretically by examining two types of grasps on cylinders; 1) fingertip grasps using three independently operated fingers, and 2) single-finger power grasps with one contact point on each of three links. Constraint maps are generated for various fingertip grasps in order to show how proper placement of the grasp …

A Low-Cost Part-Task Flight Training System: An Application Of A Head Mounted Display, David A. Dahn

Theses and Dissertations

To investigate the feasibility of using head-mounted display(HMD) and Computer Image Generators(CIG) in a low cost part-task trainer, we created a prototype system. Our approach was to build a virtual world interface using a HMD to an existing flight simulator application. This allowed a CIG with only one graphics channel to drive the display. To investigate which class of computing platform was suitable for use as the CIG, a cooperative thesis effort was launched to host the simulator on a mini-computer and micro-computer platform. The appropriate CIG could then be determined through demonstration and comparison between the systems. A software …

An Empirical Evaluation Of Analytical Models For Parallel Relational Database Queries, Mark C. Denham

Theses and Dissertations

This thesis documents the design and implementation of three parallel join algorithms to be used in the verification of analytical models developed by Kearns. Kearns developed a set of analytical models for a variety of relational database queries. These models serve as tools for the design of parallel relational database system. Each of Kearns' models is classified as either single step or multiple step. The single step models reflect queries that require only one operation while the multiple step models reflect queries that require multiple operations. Three parallel join algorithms were implemented based upon Kearns' models. Two are based upon …

An Empirical Study Of Combining Communicating Processes In A Parallel Discrete Event Simulation, Ann K. Lee

Theses and Dissertations

The primary goal of distributed discrete event simulations is to achieve speedup in simulation execution time by distributing the processing of the simulation over multiple processors. When partitioned for distribution in this fashion, simulations are typically partitioned such that there are more processes than processors. This thesis reviews existing methods for distributed discrete event simulations, and proposes general guidelines for efficient partitioning for a given communications topology based on empirical evidence. A performance analysis is conducted for two approaches to partitioning the system. The first method chosen is a mapping of multiple processes to a processor and the second approach …

Determining Concurrency In Object-Oriented Design Of Real-Time Embedded Systems Using Ada, Kenneth D. Baum

Theses and Dissertations

One of the characteristics of real-time systems is concurrency. Designers of real-time systems have traditionally determined system concurrency at implementation time using the facilities of a cyclic executive. With the advent of programming language constructs for specifying concurrency, determining concurrency at design time has become a possibility. Several design methods, all of which are extensions of either Structured Design or Jackson System Development, provide heuristics to help the designer make concurrency decisions. The object-oriented approach, however, has no corresponding heuristics to aid designers of real-time systems. The purpose of this thesis was to develop heuristics to help designers make concurrency …

Access And Operator Methods For The Triton Nested Relational Database System, Tina M. Harvey

Theses and Dissertations

Unique database requirements in the realm of non-standard applications (such as computer-aided design (CAD), computer-aided software engineering(CASE), and office information systems (OIS) have driven the development of new data models and database systems based on these new models. In particular, the goal of these new database systems is to exploit the advantages of complex data models that are more efficient (in terms of time and space) than their relationship counterparts. This research effort describes the relational design and implementation of the Triton nested relational database system, a prototype system based on the nested relational data model. Triton is intended to …