Physical Sciences and Mathematics Commons^™

Estimation Of A Water Budget For Agnes Marsh, Grand Forks County, North Dakota, Allen E. Comeskey

Theses and Dissertations

Agnes Marsh is a semipermanent wetland in the Red River Valley of northeastern North Dakota. The marsh overlies and is in direct hydraulic connection with the unconfined Elk Valley aquifer. Recent irrigation development nearby raised concerns about the hydrological impact to the marsh by a declining water table in the aquifer. The purpose of this study was to determine how Agnes Marsh interacts with the underlying Elk Valley aquifer and how sensitive the marsh is to declining water levels in the aquifer.

Three methods were used to assess how the marsh interacts with the aquifer. First, stratigraphic analysis revealed the …

Weapon System Integration For The Afit Virtual Cockpit, William E. Gerhard Jr.

Theses and Dissertations

The Air Force Institute of Technology is continuing research in the Virtual Cockpit. The Virtual Cockpit makes use of high performance graphics workstations, Virtual Environment technology, and Distributed Interactive Simulation network protocols to create a flight simulator based on the capabilities of the McDonnell Douglas F-15E Strike Eagle. The work presented in this thesis focuses on the design and implementation issues for integrating a weapons delivery capability. Weapons simulated include: RADAR and IR guided air- to-air missiles, gravity and precision guided bombs, and a 20mm cannon. Virtual Environment displays used include: color NTSC and monochrome high resolution helmet mounted displays …

Power Analysis In Flexible Automation, Nathan A. Titus

Theses and Dissertations

The performance of an automation or robotic device can be measured in terms of its power efficiency. Screw theory is used to mathematically define the task instantaneously with two screws. The task wrench defines the effect of the device on its environment, and the task twist describes the motion of the device. The tasks can be separated into three task types: kinetic, manipulative, and reactive. Efficiency metrics are developed for each task type. The output power is strictly a function of the task screws, while device input power is shown to be a function of the task, the device Jacobian, …

Data Reduction With Least Squares Differential Correction Using Equinoctial Elements, Michael S. Wasson

Theses and Dissertations

This study investigates earth satellite orbit estimation on a track of range, azimuth, and elevation data from a single tracking station. The estimation routine is a least squares batch filter based solely on two-body orbital motion. Using equinoctial elements for the reference orbit avoids the numerical difficulties of the classical elements at eccentricities near zero and inclinations near zero or 90 degrees. Orbits for Mir, DMSP, Explorer, Cosmos, and GPS are investigated. The goal of this study is to reduce orbit information from observations (range, azimuth, and elevation) to an element set and a covariance matrix without considering perturbation effects. …

Optimal Control Of The Starfire Beam Director, Troy V. Lanier

Theses and Dissertations

The Starfire Beam Director (SBD) is located at the Starfire Optical Range at Kirtland Air Force Base in Albuquerque, New Mexico. The SBD capabilities include tracking celestial objects and active or passive tracking of artificial satellites to support the Phillips Laboratory Ground Based Laser Acquisition, Tracking, and Pointing (GBL ATP) program. The pointing and tracking accuracy needed to support such experiments is micron rad to sub-grad level. To accomplish this goal requires precise pointing of the massive 6 ton 1 -meter clear aperture coelostat. The purpose of this thesis is to use optimal control design techniques to develop a controller …

Object-Oriented Analysis, Design, And Implementation Of The Saber Wargame, David S. Douglass

Theses and Dissertations

Saber is a two-sided, air and land war game that simulates decisions made of commanders at the theater-level. It is being developed by the Air Force Institute of Technology for the Air Force Wargaming center at Maxwell AFB, Alabama. Saber models conventional, chemical, and nuclear warfare between aggregated air and land forces. It also portrays the effects of logistics, satellites, weather, terrain, and intelligence which add to the realism of the Saber war game. The Saber war game has three main components, the preprocessor. which is responsible for scenario development and pregame activities, the simulation. the guts of the war …

A Vhdl Interpreter For Model-Based Diagnoses, David R. Griffin

Theses and Dissertations

Model-based reasoning permits diagnostic applications to be written without waiting for someone to become an 'expert' of the system. For model-based diagnostics, there must be a model to reason from. This thesis explores using a VHDL description of the system as that model. A system based around a VHDL interpreter was written specifically for a model-based diagnostic algorithm. Currently, the diagnostic system uses an algorithm by Dries. This algorithm was derived from Scarl's Full Consistency Algorithm. The system was designed to be modular so that different diagnostic techniques could be implemented. It is divided into three parts: a VHDL parser, …

A User Interface To A True 3-D Display Device, Bruce A. Hobbs

Theses and Dissertations

This thesis describes an interactive interface to a true three dimensional, real-dm dynamic graphic display, the TI Omniview™. The system generates true 3-D images of volumetric data and objects. The TI Omniview is a cylindrical volumetric laser display that uses a rotating double-helix translucent disk to fill the display cylinder. Voxels are illuminated on the 2-D surface. The rotational speed of the disk allows the viewer to fuse the 2-D images into a true 3-D image. The interface provides the user with a quick and flexible means of manipulating the image generated, the sub-volume displayed, and the resulting 3-D image. …

Solution To A Multicriteria Aircraft Routing Problem Utilizing Parallel Search Techniques, James J. Grimm Iii

Theses and Dissertations

Pilots select routes based on factors such as threats, fuel, time on target, distance, and refueling points. This is a time consuming task. This thesis presents the software engineering synthesis of a software tool, based on a parallelized A* search algorithm, to select routes. For simplicity only threats and distance are used. A centralized open list is used with one processor managing the list while the other processors perform the node expansions. This decomposition result in a dynamically load balanced system. A number of parameters are changed to study their impact on the execution time. The use of a branch …

An Investigation Of Discovery-Based Learning In The Route Planning Domain, Freeman A. Kilpatrick Jr.

Theses and Dissertations

This thesis presents MAVERICK, a Discovery-Based learning (DBL) system designed to learn maneuvers in the route planning domain. DBL was originally designed to learn in domains for which little domain knowledge exists. This thesis proposes using it in domains for which knowledge exists, but the acquisition of this knowledge is difficult or time-consuming because of the knowledge acquisition bottleneck. The operation of the DBL process in MAVERICK was investigated to determine the potential utility of such a system to a real- world Air Force problem in the domain of aircraft route planning. MAVERICK worked well in its limited domain, and …

Generalization And Parallelization Of Messy Genetic Algorithms And Communication In Parallel Genetic Algorithms, Laurence D. Merkle

Theses and Dissertations

Genetic algorithms (GA) are highly parallelizable, robust semi- optimization algorithms of polynomial complexity. The most commonly implemented GAs are 'simple' GAs (SGAs). Reproduction, crossover, and mutation operate on solution populations. Deceptive and GA-hard problems are provably difficult for simple GAs. Messy GAs (MGA) are designed to overcome these limitations. The MGA is generalized to solve permutation type optimization problems. Its performance is compared to another MGA's, an SGA's, and a permutation SGA's. Against a fully deceptive problem the generalized MGA (GMGA) consistently performs better than the simple GA. Against an NP-complete permutation problem, the GMGA performs better than the other …

Examining A Layered Approach To Function And Design Representation For Reusable Software Components, Paul D. Siebels

Theses and Dissertations

This effort examined ways to improve the effectiveness of reusable software libraries. The main area of investigation was in improving the user interface by finding better ways to present the software components to potential re-users. The first aspect which was considered was finding an effective representation for reusable software components. A set of criteria was developed for evaluating the effectiveness of software representations. The criteria consisted of generality, expressiveness, understandability, consistency, and resolution. The second aspect which was considered was how to present the software component information to the user to facilitate finding the appropriate component for reuse. A representation …

An Intelligent Real-Time System Architecture Implemented In Ada, Michael A. Whelan

Theses and Dissertations

Conventional real-time systems are fully deterministic allowing for off-line, optimal, task scheduling under all circumstances. Real-time intelligent systems add non-deterministic task execution times and non- deterministic task sets for scheduling purposes. Non-deterministic task sets force intelligent real-time systems to trade-off execution time with solution quality during run-time and perform dynamic task scheduling. Four basic design considerations addressing those tradeoffs have been identified: control reasoning, focus of attention, parallelism, and algorithm efficacy. Non-real- time intelligent systems contain an environment sensor, a model of the environment, a reasoning process, and a large collection of procedural processes. Real-time intelligent systems add to these …

Creating And Manipulating Formalized Software Architectures To Support A Domain-Oriented Application Composition System, Cynthia G. Anderson

Theses and Dissertations

This research investigated technology which enables sophisticated users to specify, generate, and maintain application software in domain-oriented terms. To realize this new technology, a development environment, called Architect, was designed and implemented. 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 depends upon the existence of a formal object base (or domain model) which was investigated by another student in related research. The research described in this thesis relied on …

A Model For Determining Task Set Schedulability In The Presence Of System Effects, Rusty O. Baldwin

Theses and Dissertations

This research developed a parameterized model that accounts for system overhead and determines when an Ada runtime environment can no longer successfully execute a given Ada task set and still meet all deadlines. The Ada Compiler Evaluation Capability benchmark was used to characterize an actual runtime environment. Using that data, a generic model of a preemptive, rate monotonic priority based runtime system was developed which accounts for overhead due to clock updates, context switching, task suspension, and synchronization. Validation was based on the Hartstone benchmark. First, the benchmark was executed using, the actual runtime environment. Then, those results were compared …

Spatial Partitioning Of A Battlefield Parallel Discrete-Event Simulation, Kenneth C. Bergman

Theses and Dissertations

This thesis describes a method for spatially partitioning a battlefield into units known as sectors to achieve speedup two ways: through the reduction of each battlefield object's next event search space, and lowering the amount of message-passing required. Each sector is responsible for tracking and controlling access to all objects within its boundaries. A distributed proximity detection algorithm employing boundary-crossing events is used to control player movement between sectors. Each object's state information is replicated in all sectors it has sensor capability for the minimum time required; -this ensures that each object's next event is properly determined based upon interactions …

Formalization And Transformation Of Informal Analysis Models Into Executive Refine™ Specifications, Mary M. Boom, Bradley D. Mallare

Theses and Dissertations

This research developed and implemented an automated technique for translating informal specifications into formal, executable specifications. A unified Abstract Model (UAM) was developed to combine the information contained in Entity Relationship, State Transition, and Data Flow Models into a concise, object-based representation. The UAM forms the basis for defining a formal language, the Object Modeling Language (OML), used to capture the information contained in the UAM. By using OML, we were able to develop an automated translation process to convert informal specifications into executable, formal specifications. The Software Refinery Development Environment enabled us to easily develop a parser that translates …

Version And Transaction Management In Osmagic: An Object-Oriented Database Implementation Of The Magic Vlsi Layout Design Tool, Gary M. Lightner

Theses and Dissertations

The goal of this thesis was to study the feasibility of using an object-oriented database management system to provide the functionality and performance needed to support a complex computer-aided design tool. We do this by modifying OSMagic, a prototype system of the Magic very large scale integrated (VLSI) circuit design tool implemented on the ObjectStore object- oriented database management system. OSMagic was changed to support three different interfaces to ObjectStore and to work in a networking environment. We then designed and examined the use of version and transaction management models as a means of addressing the weaknesses of the prototype …

Efficient Derivation And Approximations Of Cepstral Coefficients For Speech Coding, Kimberly A. Limcangco

Theses and Dissertations

A new formulation is presented for the calculation of cepstral coefficients directly from measured sine wave amplitudes and frequencies of speech waveforms. Approximations to these cepstral coefficients are shown to be suitable for operation in a real-time speech coding environment. These results were encoded in the C programming language and then evaluated through experiments that were conducted on the McAulay-Quatieri Sinusoidal Transform Coder (STC).

A Unified Model Of Program Behavior, Douglas T. Michel

Theses and Dissertations

This thesis is an attempt to account for and unify the three types of locality: temporal, spatial, and structural. A diverse sample of traces are used in measuring program behavior with respect to these localities and a model is presented which represents the memory references a program generates as it goes through execution. The model is validated by estimating, the entropy of a synthetically generated trace and comparing it with actual traces. The results indicate that there is more predictability contained in the original trace than what the model was able to capture. Different variations of the model were tried …

An Enhanced User Interface For The Saber Wargame, Donald R. Moore

Theses and Dissertations

This thesis is part of an on-going effort by the Air Force Institute of Technology to develop a computer-based, theater-level wargame for the Air Force Wargaming Center at Maxwell AFB, AL. The wargame, Saber, is intended to augment the education the students receive at the Air War College and the Air Command and Staff College in the employment of air and ground power. This thesis documents the integrated design and implementation of the two components of the Saber user interface: the pre-processor and the post-processor. Although previous thesis students designed and implemented substantial portions of the user interface, a fully …

Ada Implementation Of An Object Data Repository, Stephen P. Perucca

Theses and Dissertations

The many benefits of object-oriented software development such as encapsulation and extendibility have inspired numerous models of the object- oriented paradigm. Rumbaugh's Object Modeling Technique (OMT) is an object- oriented model that uses three submodels. The object, dynamic, and functional submodels of the OMT describe the data, behavioral, and processing aspects of a system by using entity-relationship, state-transition, and data flow models. Cross-links relate how the three submodels tie together. Two metamodels (models of models) of the OMT are developed using the OMT methodology and notation. The essential data elements of the OMT are abstracted into a data metamodel, and …

A Synthetic Environment For Satellite Modeling And Satellite Orbital Motion, David L. Pond

Theses and Dissertations

Analysts tasked to study satellites moving in space must often rely on photographs to conduct their analysis. Often these photographs do not adequately represent how satellites move in space, their spatial relationships, or their interaction with other satellites. What analysts need is a three- dimensional synthetic environment that depicts satellites as they actually move and interact in space. This thesis addresses the early development of the Satellite Modeler (SM), a system that allows analysts to study, satellite motion and maneuvering of computer aided design (CAD) models of those satellites in a three-dimensional orbit. The system contains equipment that allows analysts …

Creating And Manipulating A Domain-Specific Formal Object Base To Support A Domain-Oriented Application Composition System, Mary Anne Randour

Theses and Dissertations

This research investigated technology which enables sophisticated users to specify, generate, and maintain application software in domain-oriented terms. To realize this new technology, a development environment, called Architect, was designed and implemented. 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 is correctness before any programming language specific code is generated. This thesis investigated populating and manipulating the formal object base required by Architect. This object base is built using a domain- specific language (DSL) which serves as an interface between …

Entity-Relationship Versus Object-Oriented Modeling And The Underlying Dbms, Kevin J. Routhier

Theses and Dissertations

Despite the impressive accomplishments in relational database research, greater support is needed for persistence of the new types of data encountered with object-oriented programming. The concept of object-orientation is not new in the realm of programming; however, its utilization in database management systems is still immature. Regardless of this fact, there is an urgency for object-oriented database technology. With this increase in demand for the next generation databases comes the need to examine object-oriented data modeling versus the conventional entity-relationship modeling of relational database design. This thesis objective is to analyze both paradigms to determine if object-oriented modeling can significantly …

Management Of Simnet And Dis Entities In Synthetic Environments, Steven M. Sheasby

Theses and Dissertations

This thesis describes the techniques used to create an object manager utilized by an application program during a distributed interactive simulation. This work is currently utilized by a number of AFIT synthetic environment applications for use during a SIMNET exercise. An extensive review of distributed interactive simulations is presented. A discussion of the current distributed simulation protocol, SIMNET, is presented along with the future protocol standard, DIS. Finally, a brief discussion on dead reckoning and its importance during an exercise is presented. An analysis of the SIMNET and DIS protocols provided the basis for the creation of a series of …

A Synthetic Environment Flight Simulator: The Afit Virtual Cockpit, John C. Switzer

Theses and Dissertations

This thesis describes the design and implementation of a part of the Virtual Cockpit: a synthetic environment, distributed network flight simulator. The goal of the project was to prove the concept that this type of flight simulator could fill the gap between high-end, very expensive flight simulators and low-end game quality flight simulators. Discussed are: object-oriented design techniques, multi-processor utilization, the flight dynamics model, synthetic environment technology, the frame-rate vs. realism issue, and the interfaces to a realistic joystick and throttle.

X-Aaarf An X Windows Version Of The Afit Algorithm Animation Research Facility, Charles R. Wright Jr.

Theses and Dissertations

The AFIT Algorithm Animation Research Facility was developed by the Air Force Institute of Technology (AFIT) as a teaching aid for data structures and algorithm design of sequential processes. However, AAARF's unique design makes it particularly suitable for the animation of algorithms running on remote systems. In particular, an extensive set of parallel performance animations has been developed for the Intel iPSC/2 Hypercube for parallel program analysis and performance optimization. The AAARF system was originally developed using the Sun Microsystems' SunView(TM) windowing system. Recent advances in Graphical User Interface (GUI) technology combined with Sun's adoption of the X Window System …

Design Recovery For Software Library Population, Chester A. Wright Jr.

Theses and Dissertations

This thesis research investigated design recovery as a means of populating a reuse library. The targeted library was part of the Automatic Programming Technologies for Avionics Systems (APTAS). APTAS uses a knowledge base of forms, to present questions to a user, and rules, to select the forms to present and choose existing library modules to use in composing a new system. The approach applied the reengineering model developed by Eric Byrne to accomplish planning for the project, expanded the renovation phase of this model to cover the actual design recovery, and applied the expanded model to populating the library. Using …

Formalizing, Validating, And Verifying Real-Time System Requirements With Reacto And Vhdl, Frank C. Young

Theses and Dissertations

We develop a methodology for formalizing, verifying, and validating the requirements specification of real-time systems based on a graphical and formal hierarchical Finite State Machine (FSM) language Reacto. We define a means to quantify time and express real-time constraints in Reacto and a transformation from Reacto to the Very High Speed Integrated Circuit (VHSIC) hardware Description Language (VHDL). Reacto's high level abstractions, graphical nature, and theorem prover produce efficient, accurate, and easily understood specifications. We use VHDL's event driven simulation capability, concurrency, and temporal operators to thoroughly examine temporal dependencies between the state machine transitions, and to increase simulation power …