Digital Commons Network^™

The Standardized Influence Matrix And Its Applications To Generalized Linear Models, Jiandong Lu

Theses and Dissertations

The standardized influence matrix is a generalization of the standardized influence function and Cook’s approach to local influence. It provides a general and unified approach to judge the suitability of statistical inference based on parametric models. It characterizes the local influence of data deviations from parametric models on various estimators, including generalized linear models. Its use for both robustness measures and diagnostic procedures has been studied. With global robust estimators, diagnostic statistics are proposed and shown to be useful in detecting influential points for linear regression and logistic regression models. Robustness of various estimators is compared via. the standardized influence …

Validation Of A Virginia Work Release Risk Prediction Model: A Methodology For The Improvement Of The Reliability Of Correctional Decision Makers, William Nathan Osborne Jr.

Theses and Dissertations

This study identifies and validates variables which are significant predictors of work release success on 439 Virginia work release participants. The variables were selected on the basis of whether they would exert internal or external control over the inmate, with a view toward offering empirical support to control theory. A retrospective longitudinal research design was employed by randomly selecting inmates who had participated in either of three work release centers from 1987 to 1991. Two of the programs housed male inmates while the other housed female inmates. Data were collected from inmate files on thirty-one variables over a six month …

Trust In A Medical Expert System: An Exploratory Study, Anthony John Moffa

Theses and Dissertations

Operator trust in the abilities of an expert system can be crucial, especially in a high risk setting like the medical field. No studies have attempted to measure trust in a medical diagnostic aid. In the present research, diagnostic agreement and number of trials of an abdominal pain diagnostic aid were manipulated. The scenarios and feedback of the diagnostic aid were limited for purposes of control. Participants entered cases into the computer-based aid. Effects on operators’ trust were measured subjectively. The trust metric consisted of an overall trust question as well as questions representing two models of trust between humans …

Einstein's Equations In Vacuum Spacetimes With Two Spacelinke Killing Vectors Using Affine Projection Tensor Geometry, Miles D. Lawrence

Theses and Dissertations

Einstein's equations in vacuum spacetimes with two spacelike killing vectors are explored using affine projection tensor geometry. By doing a semi-conformal transformation on the metric, a new "fiducial" geometry is constructed using a projection tensor fields. This fiducial geometry provides coordinate independent information about the underlying structure of the spacetime without the use of an explicit form of the metric tensor.

A Vision From Locksley Hall : American Air Power From Kitty Hawk To Schweinfurt, Leif H. Urseth

Theses and Dissertations

No abstract provided.

Self-Managed Teams And Traditional Pyramid Management : Attitudes Of Extension Field Educators, S D. Anderson

Theses and Dissertations

No abstract provided.

An Integer Programming Model And An Experimental Study For The Design Of Cellular Manufacturing Systems, Catherine Roze

Theses and Dissertations

No abstract provided.

Pencils Of Plane Curves And Exact Orbits Of Green Function Renormalization Maps For Hierarchical Lattices, Christopher C. Reese

Theses and Dissertations

No abstract provided.

A Test Battery Of Visuospatial Ability And Contrast Sensitivity Of Instrument Pilots As A Measure Of Predicted Pilot Performance, Paulette Marie Stronczek

Theses and Dissertations

No abstract provided.

Analysis, Design, And Implementation Of A Modified Fuzzy Logic Controller, Sudjono Tandio

Theses and Dissertations

No abstract provided.

Artificial Intelligence As It Applies To Industrial Process Control, Robert G. Strain

Theses and Dissertations

No abstract provided.

The Characterization And Preparation Of Single Crystal Molybdenum Disulfide As A Model Catalyst, Susan L. Peterson

Theses and Dissertations

No abstract provided.

Gasifier Modeling Using Neural Networks, C Narahari Rao

Theses and Dissertations

No abstract provided.

A High Resolution Gravity Survey For The Detection Of Pleistocene Aquifers Underlying The Fort Berthold Indian Reservation, North Dakota, Mark R. Mcdonald

Theses and Dissertations

A high resolution gravity survey was performed over portions of McLean, Mountrail, and Ward Counties in central North Dakota during the fall and winter of 1990-1991. The study was performed to locate and map Pleistocene sand and gravel aquifers. Well data indicate that aquifers beneath the study area range in thickness from 1 to 60 meters. The Bouguer gravity anomalies resulting from these shallow aquifers was estimated to be on the order of 1 to 2 mgals. Previous studies have focused on available well data and by mapping topographic lows. Due to the inferential nature of these studies, the detailed …

A Comparison Of Wellhead Protection Area Delineation Methods At Larimore, North Dakota, Barbara L. Sahl

Theses and Dissertations

Many communities in North Dakota rely on water from shallow, unconfined aquifers that are vulnerable to contamination. A strategy to protect public groundwater supplies is the delineation of wellhead protection areas (WHPAs) around the area which contributes water to a well. Several delineation methods are available, all of which have simplifying assumptions which affect the size or shape of a predicted WHPA.

Five WHPA delineation methods were compared to determine which simplified the aquifer/well system while preserving essential hydrogeologic features. A simple system may not require a complex model to predict an accurate WHPA. Sensitivity of each to changes in …

Preferential Flow Mechanisms : Their Interaction And Effect On Dye Movement In Till And Glaciolacustrine Sediment, Calvin D. Taylor

Theses and Dissertations

Contamination of groundwater by agricultural chemicals is of concern to the population of the Northern Great Plains. Preferential flow (macropore, finger, and funnel) allows such chemicals to move relatively rapidly through materials considered to be aquitards. Preferential flow mechanisms at two sites in North Dakota, one in till, the other in glaciolacustrine sediments were determined by application of blue dye (FD&C No 1) solution to framed sites (9m2 & 4m2) with the topsoil removed. The sites were then cored and blocks hand-excavated to depths of 1.5 and 2.5-meters. The three types of preferential flow (macropore, finger, and funnel) were analyzed …

Diagenetic Controls Of Reservoir Quality In The Mississippian Wayne Beds In The Williston Basin, Bottineau County, North Dakota, Michael M. Wetmore

Theses and Dissertations

The carbonate Wayne beds of the Frobisher-Alida interval (Mississippian Mission Canyon Formation) in the Williston Basin, North Dakota, are capable of producing as much as 400,000 barrels of oil per well at depths of only 3,100 feet. Wayne production is from structural traps in the intertidal packstone-wackestone lithofacies; however, the ultimate recoverable reserves of oil per well is controlled neither by structure, nor by depositional environments.

The Wayne beds underwent cementation and micritization in the marine phreatic diagenetic environment. Hypersaline diagenesis caused minor dolomitization and anhydritization. Dissolution and minor cementation occurred in the freshwater vadose zone. Freshwater phreatic diagenesis resulted …

Isostatic Rebound In The Lake Agassiz Basin Since The Late Wisconsinan, Eric C. Brevik

Theses and Dissertations

This study addressed three main questions: I) how thick was the ice that covered the southern Lake Agassiz basin during the Wisconsinan and how much that ice depressed the crust, 2) how much rebound has occurred since deglaciation and whether or not rebound is complete, and 3) what were the effects of this rebound on the basin.

The most direct method of measuring rebound in the Lake Agassiz basin is from strandlines left by glacial Lake Agassiz. The oldest complete strandline, the Herman, presumably rebounded, with the northern end rebounding more because the ice was thicker there and had melted …

Evaluation Of A Possible Subsurface Impact Crater: The Newporte Structure, Northwestern Renville County, North Dakota, Timothy R. Gerlach

Theses and Dissertations

The purpose of this study was to determine if enough evidence exists to support an impact origin hypothesis the Newporte structure. Newporte, a petroliferous, subsurface, crater-shaped feature is located one mile south of the North Dakota - Saskatchewan border in Renville County. It is evident in Precambrian through Ordovician strata at depths of 9100 to 9600 ft (2774 to 2926 m) structure is approximately 2.0 miles (J.2 km) in diameter. Shell Oil company discovered Newporte field when testing this seismically-defined structure in 1977.

Seismic reflection profiling data and synthetic seismograms were used to generate maps that confirmed the circularity of …

A Prototype Architecture For An Automated Scenario Generation System For Combat Simulations, Mark W. Pfefferman

Theses and Dissertations

This research effort examines the problem of automating the scenario generation process and presents a prototype architecture for an automated scenario generation system. This architecture is designed using an object- oriented approach which leads to a modular and modifiable design. The architecture provides a mechanism for automatically generating scenario files from a textual US Army operation order. This translation process occurs in two phases. First, the text operation order is translated into an intermediate format called the mission file. In the second phase, the system reads the mission file, instantiates intelligent entities, and assigns missions to those entities. The intelligent …

Objectsim - A Reusable Object Oriented Dis Visual Simulation, Mark I. Snyder

Theses and Dissertations

This research designed and implemented a reusable Distributed Interactive Simulation DIS visual simulation architecture for Silicon Graphics platforms. The goal was to research software architecture technologies and to create a design and implementation using these ideas. The architecture was designed using object oriented techniques to provide the ability to customize it via inheritance extension. The resulting design was implemented using C and applied to several DIS visual simulation projects in the Graphics Lab at AFIT. The architecture, named ObjectSim, was successful in its goal of providing a reusable core for the DIS visual simulation projects in the Graphics Lab at …

Design Of A Shared Coherent Cache For A Multiple Channel Architecture, John A. Reisner

Theses and Dissertations

The Multiple Channel Architecture MCA is a recently proposed computer architecture which uses fiber optic communications to overcome many of the problems associated with interconnection networks. There exists a detailed MCA simulator which faithfully simulates an MCA system, however, the original version of the simulator did not cache shared data. In order to improve the performance of the MCA, a cache coherency protocol was developed and implemented in the simulator. The protocol has two features which are significant: (1) a time-division multiplexed TDM communication bus is used for coherency traffic, and (2) the shared data is cached in an independent …

Graphical Tools For Situational Awareness Assistance For Large Battle Spaces, Brian B. Soltz

Theses and Dissertations

As virtual environments grow in complexity and size, users are increasingly challenged in assessing situations in large-scale virtual environment. This occurs because of the difficulty in determining where to focus attention and assimilating and assessing the information as it floods in. One technique for providing this type of assistance is to provide the user with a first-person, immersive, synthetic environment observation post, that permits unobtrusive observation of the environment without interfering with the activity in the environment. However, for large, complex synthetic environments, this type of support is not sufficient because the portrayal of raw, unanalyzed data in the virtual …

Object Interaction In A Parallel Object-Oriented Discrete-Event Simulation, Walter G. Trachsel

Theses and Dissertations

This thesis investigates object interaction issues involved in developing an object-oriented parallel discrete-event simulation and develops a simulation model that provides object interaction capabilities. The research covers issues in object representation, object interaction, object management. discrete-event simulation, and parallel simulation. There are three primary types of objects that the research discusses. The first type is a basic simulation object, whose size and behavior is insignificant compared to the size of the simulation as a whole. The second type is an aggregate object which consists of smaller component objects that interact and affect the performance of the larger object as a …

Domain Modeling Of Time-Dependent Systems, Robert W. Waggoner

Theses and Dissertations

This research investigated the feasibility of composing time-dependent specifications in Architect, a domain-oriented application composition and generation system being developed at the Air Force Institute of Technology (AFIT). Architect composes formally specified domain objects into an executable software specification that can be used to verify program correctness prior to generation of language specific code. As part of this research, domain modeling techniques were investigated and a candidate process was selected for evaluation. The process was used to develop domain models for two diverse time-dependent domains. Using object-oriented analysis, formal specifications were developed for a collection of event-driven logic circuit components …

A Method For Populating The Knowledge Base Of Afit's Domain-Oriented Application Composition System, Russell M. Warner

Theses and Dissertations

This research developed a formal method for adding new domains to Architect, a domain-oriented application composition system being developed at the Air Force Institute of Technology AFIT to explore new software engineering technologies. Using canonical formal specifications of domain objects, Architect rapidly composes these specifications into a software application and executes a prototype of that application as a means to demonstrate its correctness before any programming language specific code is generated. Architect is implemented in the Software Refinery environment, which allows Architect to create and manipulate object-oriented specifications. As a part of this research effort, domain-oriented application composition systems were …

Domain Analysis And Modeling Of A Model-Based Software Executive, Robert L. Welgan

Theses and Dissertations

This research was adapted the domain analysis techniques of Prieto- Diaz and Tracz to specify a domain analysis process which was used to conduct domain analysis over the domain of software executives. This analysis created a set of informal and formal domain model artifacts. The domain model artifacts were instantiated into two application executive subsystems. These executive subsystems operated in Architect, a domain-oriented application composition system based on the Object-Connection-Update OCU model. This research demonstrated and evaluated execution of the instantiated executive domain model in a series of event-driven and time-driven applications. As a consequence of developing the application executive …

Synthetic Battlebridge: Information Visualization And User Interface Design Applications In A Large Virtual Reality Environment, Kirk G. Wilson

Theses and Dissertations

With shrinking budgets and fewer personnel, future military training will rely heavily on simulated environments. The goal for this training is to reduce cost while maintaining readiness and unparalleled capability for all levels of military command. This thesis effort, the Synthetic Battle Bridge SBB , provides a real-time simulated environment for military commanders to observe on-going computer simulations of varying participation levels and helps them wring the most from a simulation. The SBB, designed for higher ranking personnel with little time to spend learning how to run the system, must exhibit three capabilities ease-of-use, long-term retention, and adaptability. Based on …

Evaluation Of Moderate Angle Of Attack Roll Of A Dual Engine, Thrust Vectoring Aircraft Using Quantitative Feedback Theory, Kevin E. Boyum

Theses and Dissertations

This thesis develops an innovative approach to the design of a flight control system for performing the large-amplitude velocity vector roll maneuver at high angles of attack AOAs. A six degree of freedom aircraft model is developed from the fundamental nine-state equations of motion using a modified linearization technique. The MIMO multiple-input multiple-output Quantitative Feedback Theory QFT robust control design technique is then used to jointly address the system nonlinearities present in this maneuver and the changes in the system parameters due to changes in flight condition, treating them as structured uncertainty in the design of a three-axis rate-commanded control …

Three Dimensional Object Recognition Using A Complex Autoregressive Model, David E. Chelen

Theses and Dissertations

Based on an autoregressive model, Complex Partial Correlation CPARCOR features are known to provide exceptional Position, Scale, and Rotation Invariant PSRI properties for planar 2-Dimensional 2-D object recognition. Although autogressive models have been successfully applied to numerous spatio-temporal recognition tasks, the effects of out-of-plane image rotations were never considered. This study investigates application of the CPAR-COR model to a five class problem of nonplanar 2-D views of 3-D objects. Recognition based on CPAR-COR features is evaluated using a Template Matching algorithm, two K-Nearest-Neighbor KNN classifiers, and a Hidden Markov Model HMM. Direct comparisons to recognition based on Fourier features are …