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Air Force Institute of Technology

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Estimation Of Satellite Orientation From Space Surveillance Imagery Measured With An Adaptive Optics Telescope, Gregory E. Wood Dec 1996

Estimation Of Satellite Orientation From Space Surveillance Imagery Measured With An Adaptive Optics Telescope, Gregory E. Wood

Theses and Dissertations

The use of the matched filter to automatically estimate the pose of a Low Earth Orbiting satellite from imagery taken with an adaptive optics telescope is explored. This work represents the first effort to solve the satellite pose estimation problem while considering the broad range of atmospheric turbulence levels and target visual magnitudes that are encountered in ground based space surveillance operations. Several Algorithms are examined in an effort to determine the performance bounds on the matched filter for this application. Results are given over an extremely wide range of seeing conditions. These results are weighted based on historical data …

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The Capacity Of The Air Force Satellite Control Network, Kwangho Jang Dec 1996

The Capacity Of The Air Force Satellite Control Network, Kwangho Jang

Theses and Dissertations

The daily mission objective of the Air Force Satellite Control Network (AFSCN) is to support communication with satellite systems. It is critical that the AFSCN operate 24 hours a day, seven days a week. Previous work on the satellite range scheduling problem has successfully scheduled over 90 percent of the satellite support requests. This research investigates the capacity of the AFSCN using an available satellite scheduling algorithm. This research has three objectives. The first objective is to be able to generate sample data sets which represent a day of satellite support requests for low, medium, and high altitude satellites. The …

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Countering The Effects Of Measurement Noise During The Identification Of Dynamical Systems, Odell R. Reynolds Dec 1996

Countering The Effects Of Measurement Noise During The Identification Of Dynamical Systems, Odell R. Reynolds

Theses and Dissertations

Sensor noise is an unavoidable fact of life when it comes to measurements on physical systems, as is the case in feedback control. Therefore, it must be properly addressed during dynamic system identification. In this work, a novel approach is developed toward the treatment of measurement noise in dynamical systems. This approach hinges on proper stochastic modeling, and it can be adapted easily to many different scenarios, where it yields consistently good parameter estimates. The Generalized Minimum Variance algorithm developed and used in this work is based on the theory behind the minimum variance identification process, and the estimate produced …

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Algebraic Algorithm Design And Local Search, Robert P. Graham Jr. Dec 1996

Algebraic Algorithm Design And Local Search, Robert P. Graham Jr.

Theses and Dissertations

Formal, mathematically-based techniques promise to play an expanding role in the development and maintenance of the software on which our technological society depends. Algebraic techniques have been applied successfully to algorithm synthesis by the use of algorithm theories and design tactics, an approach pioneered in the Kestrel Interactive Development System (KIDS). An algorithm theory formally characterizes the essential components of a family of algorithms. A design tactic is a specialized procedure for recognizing in a problem specification the structures identified in an algorithm theory and then synthesizing a program. Design tactics are hard to write, however, and much of the …

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Perceptual Fidelity For Digital Color Imagery, Curtis E. Martin Dec 1996

Perceptual Fidelity For Digital Color Imagery, Curtis E. Martin

Theses and Dissertations

The problem of measuring the fidelity of digital color images in a manner that corresponds to human perceptual assessments is addressed. Experiments are performed to validate human visual system (HVS) models, which provide access to a 'perceptual space' in which visual distortions may be measured, and then a model is proposed for assessing the perceptual fidelity of digital color image. Color Mach bands are produced in the first experiment, demonstrating that, as in the brightness channel, low spatial frequency attenuation occurs in the chromatic channels of the HVS. In the second experiment, a correlation between the chromatic channels of the …

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Analysis Of Linkage-Friendly Genetic Algorithms, Laurence D. Merkle Dec 1996

Analysis Of Linkage-Friendly Genetic Algorithms, Laurence D. Merkle

Theses and Dissertations

Evolutionary algorithms (EAs) are stochastic population-based algorithms inspired by the natural processes of selection, mutation, and recombination. EAs are often employed as optimum seeking techniques. A formal framework for EAs is proposed, in which evolutionary operators are viewed as mappings from parameter spaces to spaces of random functions. Formal definitions within this framework capture the distinguishing characteristics of the classes of recombination, mutation, and selection operators. EAs which use strictly invariant selection operators and order invariant representation schemes comprise the class of linkage-friendly genetic algorithms (lfGAs). Fast messy genetic algorithms (fmGAs) are lfGAs which use binary tournament selection (BTS) with …

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Using Kriging To Interpolate Spatially Distributed Volumetric Medical Data, Stephen M. Matechik Dec 1996

Using Kriging To Interpolate Spatially Distributed Volumetric Medical Data, Stephen M. Matechik

Theses and Dissertations

Routine cases in diagnostic radiology require the interpolation of volumetric medical imaging data sets. Inaccurate renditions of interpolated volumes can lead to the misdiagnosis of a patient's condition. It is therefore essential that interpolated modality space estimates accurately portray patient space. Kriging is investigated in this research to interpolate medical imaging volumes. Kriging requires data to be spatially distributed. Therefore, magnetic resonance imaging (MRI) data is shown to exhibit spatially regionalized characteristics such that it can be modeled using regionalized variables and subsequently be interpolated using kriging. A comprehensive, automated, three-dimensional structural analysis of the MRI data is accomplished to …

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Microelectromechanical Isolation Of Acoustic Wave Resonators, James R. Reid Jr. Dec 1996

Microelectromechanical Isolation Of Acoustic Wave Resonators, James R. Reid Jr.

Theses and Dissertations

Microelectromechainical systems (MEMS) is a rapidly expanding field of research into the design and fabrication of actuated mechanical systems on the order of a few micrometers to a few millimeters. MEMS potentially offers new methods to solve a variety of engineering problems. A large variety of MEMS systems including flip-up platforms, scanning micromirrors, and rotating micromirrors are developed to demonstrate the types of MEMS that can be fabricated. The potential of MEMS for reducing the vibration sensitivity of surface acoustic wave and surface transverse wave resonators is then evaluated. A micromachined vibration isolation system is designed and modeled. A fabrication …

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Electrical Characterization Of Intrinsic And Induced Deep Level Defects In Hexagonal Sic, James D. Scofield Dec 1996

Electrical Characterization Of Intrinsic And Induced Deep Level Defects In Hexagonal Sic, James D. Scofield

Theses and Dissertations

Deep level defects in hexagonal SiC were studied using digital deep level transient spectroscopy (DLTS) methods over the temperature range of 100 to 800 deg K. New centers were found in bulk and epitaxial 6H-SiC with ionization energies between 0.38 to 1.3 eV, and levels from 0.2 to 0.856 eV were identified in 4H-SiC epitaxy. Direct correlation between inequivalent lattice sites was identified for energetic pairs associated with both vanadium and ion implanted Mg impurities. Nonradioative carrier capture mechanisms were studied and deep level trapping was found to proceed via lattice relaxation multi-phonon emission, indicating efficient electronic lattice coupling in …

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Theoretical Modeling Of Linear Absorption Coefficients In Si/Si1-Xgex Multiple Quantum Well Photodetectors, Kevin D. Greene Dec 1996

Theoretical Modeling Of Linear Absorption Coefficients In Si/Si1-Xgex Multiple Quantum Well Photodetectors, Kevin D. Greene

Theses and Dissertations

Si/Si1-xGex MQW Infrared Photodetectors offer the promise of normal incidence photodetection tunable over the range of 3-12 micrometers wavelength range at temperatures above 40 K. This system is attractive because the Si1-xGex offers greater compatibility with existing Si based signal processing circuitry. Band structures, momentum matrix elements and linear absorption coefficients are computed using a Luftinger-Kohn k/p analysis for Si/Si1-xGex quantum wells grown in the 110 direction. The absorption coefficient as a function of energy and wavelength is calculated by two methods: a delta function fit to intersubband transitions, and a …

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Performance Analysis Of A Liquid Metal Heat Pipe Space Shuttle Experiment, Timothy J. Dickinson Dec 1996

Performance Analysis Of A Liquid Metal Heat Pipe Space Shuttle Experiment, Timothy J. Dickinson

Theses and Dissertations

Future spacecraft technologies require advanced high-temperature thermal control systems. Liquid metal heat pipes are considered ideally suited for such applications. However, their behavior during microgravity operation is not yet understood. This study investigated liquid metal heat pipe performance in such an environment. Three stainless steel/potassium heat pipes were flown on space shuttle mission STS-77 in May 1996. The objectives of the experiment were characterization of the frozen startup and restart transients, comparison of flight and ground test data to establish a performance baseline for analytical model validation, and assessment of three different heat pipe designs. Heat pipe performance was characterized …

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Laser-Induced Breakdown Spectroscopy On Solution Samples Using Surface Excitation, Leonard M. Berman Dec 1996

Laser-Induced Breakdown Spectroscopy On Solution Samples Using Surface Excitation, Leonard M. Berman

Theses and Dissertations

Laser-induced breakdown spectroscopy (LIBS) is a spectroscopic technique where output from a pulsed laser is focused onto a target in order to create an intense plasma. The optical emission is characteristic of the elements in the focal volume and can be used for elemental analysis. Research on the detection of nickel in solution in addition to solvent detection of CCl4, CHCl3, C2Cl4, and C2HCl3 has been performed. Breakdown was formed at the sample surface via a Q-switched Nd:YAG laser. Initially, operation of the laser was at 1064 nm/repetition rate of 5 Hz. Experiments …

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Unfolding The High Energy Electron Flux From Crres Fluxmeter Measurements, Brian D. Mckellar Dec 1996

Unfolding The High Energy Electron Flux From Crres Fluxmeter Measurements, Brian D. Mckellar

Theses and Dissertations

The Combined Release and Radiation Effects Satellite (CRRES) was launched on 25 July 1990 to collect measurements in the earth's radiation belts. One instrument, the High Energy Electron Fluxmeter (HEEF), measured the flux of electrons in 10 channels with energies between 1 MeV and 10 MeV. The channel sensitivities, Ri(E), have been calibrated and partially re-calibrated. We explore the errors introduced in unfolding the electron flux spectrum from the channel measurements and the propagation and growth of calibration and measurement errors. Using numerical experimentation, we fold the responses with known spectra to obtain simulated measurements, add random measurement and calibration …

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Pulse Coupled Neural Networks For The Segmentation Of Magnetic Resonance Brain Images, Shane L. Abrahamson Dec 1996

Pulse Coupled Neural Networks For The Segmentation Of Magnetic Resonance Brain Images, Shane L. Abrahamson

Theses and Dissertations

This research develops an automated method for segmenting Magnetic Resonance (MR) brain images based on Pulse Coupled Neural Networks (PCNN). MR brain image segmentation has proven difficult, primarily due to scanning artifacts such as interscan and intrascan intensity inhomogeneities. The method developed and presented here uses a PCNN to both filter and segment MR brain images. The technique begins by preprocessing images with a PCNN filter to reduce scanning artifacts. Images are then contrast enhanced via histogram equalization. Finally, a PCNN is used to segment the images to arrive at the final result. Modifications to the original PCNN model are …

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Demonstrating Optical Aberration Correction With A Mems Micro-Mirror Device, Shaun R. Hick Dec 1996

Demonstrating Optical Aberration Correction With A Mems Micro-Mirror Device, Shaun R. Hick

Theses and Dissertations

This research conducted the first demonstrated use of a micro-electro-mechanical structure (MEMS) mirror array to correct a static optical aberration. A well-developed technique in adaptive optics imaging systems uses a deformable mirror to reflect the incident wave front to the imaging stage of the system. By matching the surface of the deformable mirror to the shape of the wave front phase distortion, the reflected wave front will be less aberrated before it is imaged. Typical adaptive optics systems use piezo-electric actuated deformable mirrors. This research used an electrostatically actuated, segmented mirror array, constructed by standard MEMS fabrication techniques, to investigate …

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Requirements, Design, And Development Of A Rapidly Reconfigurable, Photo-Realistic, Virtual Cockpit Prototype, Terry A. Adams Dec 1996

Requirements, Design, And Development Of A Rapidly Reconfigurable, Photo-Realistic, Virtual Cockpit Prototype, Terry A. Adams

Theses and Dissertations

The United States Air Force uses aircraft flight simulators for pilot training and mission rehearsal. They use a variety of simulators for this task ranging with prices ranging from $400,000 to $30,000,000. These simulators have specialized hardware that restricts reuse of their components and increases maintenance costs. Air Education and Training Command wants to reduce simulators cost and improve availability to the operational commands by supporting research in virtual reality flight simulators. This thesis looks at the development of a reconfigurable virtual cockpit in a distributed virtual environment that can be used for different aircraft as well as training scenarios. …

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Data-Driven Process Discovery: A Discrete Time Algebra For Relational Signal Analysis, David M. Conrad Dec 1996

Data-Driven Process Discovery: A Discrete Time Algebra For Relational Signal Analysis, David M. Conrad

Theses and Dissertations

This research presents an autonomous and computationally tractable method for scientific process analysis, combining an iterative algorithmic search and a recognition technique to discover multivariate linear and non-linear relations within experimental data series. These resultant data-driven relations provide researchers with a potentially real-time insight into experimental process phenomena and behavior. This method enables the efficient search of a potentially infinite space of relations within large data series to identify relations that accurately represent process phenomena. Proposed is a time series transformation that encodes and compresses real-valued data into a well-defined, discrete-space of 13 primitive elements where comparative evaluation between variables …

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Design And Prototype Of The Afit Virtual Emergency Room: A Distributed Virtual Environment For Emergency Medical Simulation, Brian W. Garcia Dec 1996

Design And Prototype Of The Afit Virtual Emergency Room: A Distributed Virtual Environment For Emergency Medical Simulation, Brian W. Garcia

Theses and Dissertations

Due to the increasing complexity of emergency medical care, medical staffs require increasingly sophisticated training systems. Virtual environments offer a low cost means to achieve a widely usable yet sophisticated training capability. The Defense Advanced Research Projects Agency (DARPA) has sponsored the Virtual Emergency Room (VER) project to develop a simulation system that enables emergency department personnel within level I and II emergency rooms to practice emergency medical procedures and protocols. The VER is a simulation facility that uses a distributed virtual environment architecture to enable real-time, multi-participant simulations. The potential advantages of this system include the ability to evaluate …

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Dynamic Relevance Filtering In Asynchronous Transfer Mode-Based Distributed Interactive Simulation Exercises, David T. Hightower Dec 1996

Dynamic Relevance Filtering In Asynchronous Transfer Mode-Based Distributed Interactive Simulation Exercises, David T. Hightower

Theses and Dissertations

As Distributed Interactive Simulation (DIS) exercises continue to grow in scale, the need to support a large number of players has become apparent. The demands on the network and the simulation hosts in large exercises, though, have proved to be prohibitive, requiring significant computational overhead to filter through the information and extract what is relevant to a particular simulation. Some mechanism is needed to reduce irrelevant network traffic received by a system, while increasing the bandwidth available for the DIS exercise. Previous research efforts in this area have centered primarily on fixed geographic partitions of the battlespace to reduce the …

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Analysis And Design Of Standard Telerobotic Control Software, Matthew L. June Dec 1996

Analysis And Design Of Standard Telerobotic Control Software, Matthew L. June

Theses and Dissertations

The Robotics and Automation Center for Excellence (RACE) has defined an open telerobotics control architecture. This architecture, called the Unified Telerobotic Architecture Project (UTAP), is a proposed standard for all Air Force telerobotic systems. Implementation of UTAP will reduce the cost of robotic applications by increasing software modularity, portability, and reusability. This thesis continued the effort to prove the feasibility of UTAP. In December, 1995, 1st Lt Anchor implemented a portion of the UTAP specification on a PUMA robot. The UTAP-compliant controller exhibited some degradation in the system performance. However, the performance degradation was not fully measured. This thesis extended …

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Refined Genetic Algorithms For Polypeptide Structure Prediction, Charles E. Kaiser Jr. Dec 1996

Refined Genetic Algorithms For Polypeptide Structure Prediction, Charles E. Kaiser Jr.

Theses and Dissertations

Accurate and reliable prediction of macromolecular structures has eluded researchers for nearly 40 years. Prediction via energy minimization assumes the native conformation has the globally minimal energy potential. An exhaustive search is impossible since for molecules of normal size, the size of the search space exceeds the size of the universe. Domain knowledge sources, such as the Brookhaven PDB can be mined for constraints to limit the search space. Genetic algorithms (GAs) are stochastic, population based, search algorithms of polynomial (P) time complexity that can produce semi-optimal solutions for problems of nondeterministic polynomial (NP) time complexity such as PSP. Three …

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Utilizing Bayesian Techniques For User Interface Intelligence, Robert A. Harrington Dec 1996

Utilizing Bayesian Techniques For User Interface Intelligence, Robert A. Harrington

Theses and Dissertations

The purpose of this research is to study the injection of an intelligent agent into modern user interface technology. This agent is intended to manage the complex interactions between the software system and the user, thus making the complexities transparent to the user. The background study will show that while interesting and promising research exists in the domain of intelligent interface agents, very little research has been published that indicates true success in representing the uncertainty involved in predicting user intent. The interface agent architecture presented in this thesis will offer one solution for solving the problem using a newly …

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A Domain Independent Framework For Developing Knowledge Based Computer Generated Forces, James L. Benslay Jr. Dec 1996

A Domain Independent Framework For Developing Knowledge Based Computer Generated Forces, James L. Benslay Jr.

Theses and Dissertations

Computer Generated Forces (CGFs) are important players in Distributed Interactive Simulation (DIS) exercises. A problem with CGFs is that they do not exhibit sufficient human behaviors to make their use effective. The SOAR approach has yielded a human cognitive model that can be applied to CGFs, but this is extremely complex. The product of the research reported in this thesis is a much less complex behavioral framework for a CGF that is easy to validate, revise, and maintain. To support this, an existing, domain independent CGF architecture is discussed and applied to an experimental CGF. Techniques for modeling the knowledge …

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Implementation Of An Ada95 Crosscompiler For The Real-Time Executive For Military Systems (Rtems), Kendall M. Lemley Jr. Dec 1996

Implementation Of An Ada95 Crosscompiler For The Real-Time Executive For Military Systems (Rtems), Kendall M. Lemley Jr.

Theses and Dissertations

This thesis represents a continuation of the assessment of the Unified Telerobotics Architecture Project (UTAP), a proposed Air Force standard. This architecture was developed by the NASA Jet Propulsion Laboratory and the National Institute of Standards under contract to the Air Force Materiel Command Robotics and Automation Center of Excellence at Kelly AFB, Texas. Due to operating system constraints, the only UTAP implementation to date has required a separate software interface layer, adding complexity and overhead to the overall system, while reducing portability. This thesis proposes a long term effort to design and implement UTAP-compliant application software devoid of this …

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Molecular Articulation In Response To Interactive Atomic Forces In Docker, Todd R. Kellett Dec 1996

Molecular Articulation In Response To Interactive Atomic Forces In Docker, Todd R. Kellett

Theses and Dissertations

Molecular docking aids in the design of materials supporting the current and future needs of the warfighter by simulating the real-world results of combining molecules. Specifically, it supports research and development in novel non-linear optical materials for laser-hardening and other advanced optical applications. Potential uses for these materials range from personnel and optical system laser protection to holographic information displays. DOCKER, our baseline docking system, minimizes the computational overhead of the simulation by modeling the molecules as rigid objects. This simplification can cause DOCKER's solutions to disagree with the real-world results, because molecules flex as they react to one another …

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Simulation Based Performance Evaluation Of Resource Allocation Algorithms For Implementation In The Shf-Dama Satellite Network, Eric P. Hobson Dec 1996

Simulation Based Performance Evaluation Of Resource Allocation Algorithms For Implementation In The Shf-Dama Satellite Network, Eric P. Hobson

Theses and Dissertations

Sponsored by DISA, the SHF-DAMA Standard addresses the warfighter's requirements for flexible, reliable, and efficient (technically and fiscally) satellite communications. The Standard proposes a system supporting both packet data transfer and single-channel-per-carrier voice and data circuits assigned on a demand basis. The Standard does not address management of the DSCS 3 transponder's bandwidth and power resources among priority classes of users. This effort characterizes the SHF-DAMA system's performance over each combination of the following resource management algorithm features: (1) preemption enabled and disabled; (2) using the Standard-specified collision resolution technique and a binary exponential backoff; (3) using complete partitioning, complete …

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Integrating The Capability Maturity Model For Software And The Quality Air Force Criteria, Marshall B. Messamore Dec 1996

Integrating The Capability Maturity Model For Software And The Quality Air Force Criteria, Marshall B. Messamore

Theses and Dissertations

As defense budgets decrease and it is required to do more with less, the Air Force has chosen to use the Malcolm Baldrige National Quality Award (MBNQA) as the basis for implementing quality principles. The Air Force program is known as Quality Air Force (QAF), and the criteria are referred to as the QAF criteria DEPA95b. At about the same time the Department of the Air Force implemented QAF, the software leaders in the Air Force adopted the Capability Maturity Model for Software (CMM) as the internal standard for Air Force software organizations MOSE9l. Software organizations strapped with both sets …

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Utilizing Data And Knowledge Mining For Probabilistic Knowledge Bases, Daniel J. Stein Iii Dec 1996

Utilizing Data And Knowledge Mining For Probabilistic Knowledge Bases, Daniel J. Stein Iii

Theses and Dissertations

Problems can arise whenever inferencing is attempted on a knowledge base that is incomplete. Our work shows that data mining techniques can be applied to fill in incomplete areas in Bayesian Knowledge Bases (BKBs), as well as in other knowledge-based systems utilizing probabilistic representations. The problem of inconsistency in BKBs has been addressed in previous work, where reinforcement learning techniques from neural networks were applied. However, the issue of automatically solving incompleteness in BKBs has yet to be addressed. Presently, incompleteness in BKBs is repaired through the application of traditional knowledge acquisition techniques. We show how association rules can be …

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A Common Architecture For Simulation Viewing Over Multiple Protocol Environments, Glenn G. Jacquot Dec 1996

A Common Architecture For Simulation Viewing Over Multiple Protocol Environments, Glenn G. Jacquot

Theses and Dissertations

This study discusses an architecture used for displaying data results in a graphical format. This data is obtained via internet connection or from a direct connection to a battlefield simulator known as BattleSim. This architecture utilizes several graphics packages for displaying the output along with two different approaches to receiving commands from the user. Furthermore, the design was built to easily incorporate other graphics packages and communication protocols in order to increase its portability.

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Solar System Modeler: A Distributed, Virtual Environment For Space Visualization And Gps Navigation, Gary E. Williams Dec 1996

Solar System Modeler: A Distributed, Virtual Environment For Space Visualization And Gps Navigation, Gary E. Williams

Theses and Dissertations

The Solar System Modeler (SM) extends the Space Modeler developed in 1994. It provides a virtual environment enabling an explorer to dynamically investigate near Earth satellites, deep space probes, planets, moons, and other celestial phenomena. The explorer navigates the virtual environment via mouse selected options from menu panels while wearing a tracked, head mounted display (HMD). Alternatively, a monitor may replace the HMD and keyboard controls replace head tracking. The SM's functionality is extended by the ability to broadcast simulated GPS satellite transmissions in compliance with Distributed Interactive Simulation (DIS) protocol standards. The transmissions include information found in true GPS …

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