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Air Force Institute of Technology

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An Improved Heuristic For Intercontinental Ballistic Missile Crew Scheduling, Michael D. Shirley Jr. Dec 1994

An Improved Heuristic For Intercontinental Ballistic Missile Crew Scheduling, Michael D. Shirley Jr.

Theses and Dissertations

Creating monthly schedules for missile crews is a complex and time-consuming problem. Thousands of events must be scheduled for several hundred missile officers. The rules and regulations governing the problem are numerous, and there are currently no established measures for missile crew schedules. The scheduling software currently available only schedules a fraction of the events. The objectives of this research were to create a rule-based heuristic which could quickly produce feasible or near-feasible schedules, to make the scheduling process paperless, and to develop possible measures of effectiveness for missile crew schedules. The research was successful in each of these areas. …

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Computing Norad Mean Orbital Elements From A State Vector, Dwight E. Andersen Dec 1994

Computing Norad Mean Orbital Elements From A State Vector, Dwight E. Andersen

Theses and Dissertations

NORAD maintains and disseminates mean orbital elements on Earth-orbiting satellites in the form of Two-Line Element Sets (TLE). Five mathematical propagator models were developed for NORAD's use to predict the position and velocity using TLEs. This study investigated two approaches, Newton's method and direct iteration, to inverting this process by iterating to obtain NORAD-compatible mean orbital elements from a position and velocity state vector and the drag term. The Newton's iteration method was developed but not tested. The less computationally intensive direct iteration method was developed, coded in FORTRAN, and tested. The initial guess and subsequent corrections in the iterative …

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Tracking And Impact Prediction Of Earth-Crossing-Objects (Ecos) On A Collision Course With Earth, Gregory A. Bishop Dec 1994

Tracking And Impact Prediction Of Earth-Crossing-Objects (Ecos) On A Collision Course With Earth, Gregory A. Bishop

Theses and Dissertations

This study investigated the effectiveness of Earth-based angles only observations in determining the orbit of various hypothetical Earth-Crossing-Objects (ECOs). 'True' trajectories were simulated specifically for Earth-Crossing- Comets (ECCs) by numerically integrating in a Restricted Three Body system. Starting at Earth impact points, the state vectors were reverse-propagated" to a proposed detection time. Observations (obs), with state-of-the-art accuracy, were then simulated with error induced by a Gaussian random number generator; these were used in a least- squares differential corrector to estimate the positions of the ECOs. State vectors and covariance matrices were then propagated to the impact times and axis lengths …

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Effects Of Photon Noise On Unconstrained Minimization Techniques For Iterative Blind Deconvolution, Derek K. Davis Dec 1994

Effects Of Photon Noise On Unconstrained Minimization Techniques For Iterative Blind Deconvolution, Derek K. Davis

Theses and Dissertations

In recent years, imaging through atmospheric turbulence has interested military scientists seeking to improve optical surveillance of satellites. Adaptive optics was a step toward achieving diffraction-limited resolution from ground-based telescopes. Unfortunately, adaptive optics only partially compensate for atmospheric blurring, therefore post processing of images is required. Processing methods in use today require knowledge of the impulse response of the optical system to reconstruct imagery, but this information is seldom known. This thesis looks at a new metal of processing compensated imagery, called blind deconvolution, which assumes very little or no a priori information about the impulse response. In particular, this …

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Optimization Of A Nutation Damper Attached To A Spin-Stabilized Satellite, Brady P. Hauboldt Dec 1994

Optimization Of A Nutation Damper Attached To A Spin-Stabilized Satellite, Brady P. Hauboldt

Theses and Dissertations

This study uses linearized equations of motion for a rigid body with an attached spring-mass-damper to maximize the decay rate of a satellite's coning motion. An analysis of the numerical eigenvalues is presented which leads to an optimal relationship between relevant parameters: damper placement, spring constant, damping coefficient, system moments of inertia, and damper mass fraction. The coupled system's eigenvalues do not provide truly critical damping, thus the real eigenvalue parts are minimized in order to achieve damping which requires the minimum amount of time. A comparison between this optimal design method and a classical method concludes a noticeable improvement …

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Generic Satellite Monitoring Expert System, Loretta A. Kelemen Dec 1994

Generic Satellite Monitoring Expert System, Loretta A. Kelemen

Theses and Dissertations

Air Force Satellite Operations is undergoing major changes. Operators no longer receive detailed satellite training, instead they are taught basic fundamentals of satellite operations and expected to control multiple multimillion dollar satellites. The need is clear. An efficient and economical automated system is necessary to assist the satellite operator in his daily tasks of maintaining these DOD priority resources. Satellite intelligent controllers been under R&D since the early 1980s to this need. These systems, however, have focused on the control of one constellation of satellites. In a military striving for efficiency and lower costs, developing a unique intelligent controller for …

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Weighting Scheme For The Space Surveillance Network Automated Tasker, Beth L. Petrick Dec 1994

Weighting Scheme For The Space Surveillance Network Automated Tasker, Beth L. Petrick

Theses and Dissertations

The purpose of this research is to find the best weighting scheme in the SPADOC 4C Sensor Tasking Prototype. This software, known as the Prototype Tasker, assigns a tasking to each sensor of the Space Surveillance Network. A tasking is a list of objects in which the sensor needs to gather positional data, called observations. One of the inputs to the Prototype Tasker is a user-definable weighting scheme. The goal is to find the weighting scheme that produces the most efficient taskings. This problem was solved using a Simulated Annealing algorithm. The values in the weighting scheme were the variables …

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A Multi-Attribute-Utility-Theory Model That Minimizes Interview-Data Requirements: A Consolidation Of Space Launch Decisions, Raymond W. Staats Dec 1994

A Multi-Attribute-Utility-Theory Model That Minimizes Interview-Data Requirements: A Consolidation Of Space Launch Decisions, Raymond W. Staats

Theses and Dissertations

This research uses multi-attribute utility theory (MAUT) to define a mathematical representation of a decision maker's utility associated with a satellite system. While developing the survey instrument, we focused on making it simpler to administer, primarily by eliminating the use of lottery questions. These simplifications enabled us to shorten our interview with the decision maker to under two hours for a rather complex model.

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A Comparison Of Error Categorization Schemes For Use In Software System Safety Programs, Richard Escobedo, Jim Thomas Dec 1994

A Comparison Of Error Categorization Schemes For Use In Software System Safety Programs, Richard Escobedo, Jim Thomas

Theses and Dissertations

Software safety is becoming increasingly important in the development of DoD advanced weapon systems. To make software safer, hazard conditions must be avoided along with the errors that accompany them. The first step in identifying errors is classifying error data. The area of software error classification is not as advanced as other software development areas. The technical literature lacks examples of comprehensive taxonomies that can be applied to various computer software domains and applications. The predominant approach is to organize errors into categories particular to the program currently in work. The typical error scheme is made of narrow categories that …

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Measurement Of N2+ Mobility In He Via Fourier Transform Emission Spectroscopy, Patrick D. Kee Dec 1994

Measurement Of N2+ Mobility In He Via Fourier Transform Emission Spectroscopy, Patrick D. Kee

Theses and Dissertations

Recently, Hong and Miller used Fourier Transform Emission (FTE) spectroscopy to determine the N2+ mobility in helium by relating the observed Doppler shift of the N2+ (B-X) transition to the measured electric field in the discharge as determined by probes. In order to establish the technique in-house, this effort duplicated that experiment and investigated the sensitivity and utility of the method. Doppler shift measurements in this experiment disagreed significantly with those reported by Hong and Miller. Attempts to reduce the data (and thus determine the mobility) using a model developed by Hong and Miller were unsuccessful. …

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Detecting Alpha Particles Through Scintillation In Porous Materials, Martin E. Keillor Dec 1994

Detecting Alpha Particles Through Scintillation In Porous Materials, Martin E. Keillor

Theses and Dissertations

This thesis presents the results of a preliminary study of parameters essential to the development of a scintillation flow-cell detector with improved characteristics over existing cells. Such a detector with better than 10% alpha energy resolution could provide in situ capability to detect and identify important alpha-emitting radionuclides in dilute aqueous solutions. Gel-silica is a potential candidate that may provide the needed improvement in resolution while maintaining 100% detection efficiency; however, gel-silica with useful light output is yet to be developed. As a step toward realizing the system described, the dependence of alpha detection efficiency and intrinsic energy resolution on …

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Analysis Of Instability Growth And Collisionless Relaxation In Thermionic Converters Using 1-D Pic Simulations, Bret B. Kreh Dec 1994

Analysis Of Instability Growth And Collisionless Relaxation In Thermionic Converters Using 1-D Pic Simulations, Bret B. Kreh

Theses and Dissertations

This work investigates the role that the beam-plasma instability may play in a thermionic converter. The traditional assumption of collisionally dominated relaxation is questioned, and the beam-plasma instability is proposed as a possible dominant relaxation mechanism. Theory is developed to describe the beam-plasma instability in the cold-plasma approximation, and the theory is tested with two common Particle-in- Cell (PIC) simulation codes. The theory is first confirmed using an unbounded plasma PIC simulation employing periodic boundary conditions, ES1. The theoretically predicted growth rates are on the order of the plasma frequencies, and ESl simulations verity these predictions within the order of …

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Feasibility Exploration Of Throughfold As A Predictor For Target Loading And Associated Error Bounds, Kris G. Rongone Dec 1994

Feasibility Exploration Of Throughfold As A Predictor For Target Loading And Associated Error Bounds, Kris G. Rongone

Theses and Dissertations

Various applications of the Fredholm integral equation appear m different fields of study. An application of particular interest to the Air Force arises in determination of target loading from nuclear effects simulations. Current techniques first unfold the incident spectrum then determine target loading; resulting spectrum and loading are assumed exact. This study investigates the feasibility of a new method, through-fold, for directly determining defensible error bounds on target loading. Through-fold uses a priori information to define input data and represents target response with a linear combination of instrument responses plus a remainder to derive a quadratic expression for exact target …

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Generation Of A Single-Lobe, Far-Field Intensity Pattern From A Laser Diode Array Using An Optical Delay Line, Thomas A. Summers Dec 1994

Generation Of A Single-Lobe, Far-Field Intensity Pattern From A Laser Diode Array Using An Optical Delay Line, Thomas A. Summers

Theses and Dissertations

A simple and practical technique is demonstrated to generate a stable, single-lobe, far-field intensity pattern from a one-dimensional, antiphased, laser diode array with gain-guided elements. The two far-field lobes of the array are combined after introducing an optical delay line into the path of one of the lobes to make the lobes mutually incoherent. The incoherent superposition of intensities produces a near-diffraction-limited, single-lobe, far-field intensity pattern containing 84% of the power, exceeding any previous (known) phase control experiments. This technique compares favorably with more elaborate schemes advanced previously using integrated phase plates, etc. The method is directly applicable to one-dimensional …

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Artificially Intelligent Air Combat Simulation Agents, Daniel E. Gisselquist Dec 1994

Artificially Intelligent Air Combat Simulation Agents, Daniel E. Gisselquist

Theses and Dissertations

The Advanced Research Projects Agency (ARPA), in an effort to improve military simulations, has proposed a standard for Distributed Interactive Simulation (DIS). This network protocol will allow dissimilar applications to communicate simulation information. In the field of air combat, this will allow pilots in remote simulators to fly in a common simulation. The success of this standard is dependent on applications being able to work within that standard, as well as a large variety of Computer Generated Forces (CGFs) to complement interactive forces. CGFs are needed to help simulate the large combat scenarios that can only occur in wartime. By …

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Unification Of Larch And Z-Based Object Models To Support Algebraically-Based Design Refinement: The Larch Perspective, Catherine J. Lin Dec 1994

Unification Of Larch And Z-Based Object Models To Support Algebraically-Based Design Refinement: The Larch Perspective, Catherine J. Lin

Theses and Dissertations

This research describes the feasibility of developing object-oriented LARCH specifications, part of a dual approach for formally extending object-oriented analysis models using LARCH and Z. The first phase consisted of two steps establishing a set of transformation heuristics for algebraically representing object models and implementing a robust LARCH parser. The LARCH parser produced abstract syntax trees ASTs of objects forming the basis for analyzing the similarities and differences between Z-based and LARCH-based object representations. The second phase used the analysis of LARCH and Z to identify fundamental core constructs in the languages and abstract syntax trees. These core constructs consisted …

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Next Generation Real-Time Systems: Investigating The Potential Of Partial-Solution Tasks, Robert E. J. Caley Dec 1994

Next Generation Real-Time Systems: Investigating The Potential Of Partial-Solution Tasks, Robert E. J. Caley

Theses and Dissertations

While the cyclic executive and fixed-priority scheduling strategies have been sufficient to handle traditional real- time requirements. they are insufficient for dealing with the complexities of next-generation real-time systems. New methods of intelligent control must be developed for guaranteeing on-time task completion for real-time systems that are faced with unpredictable and dynamically changing requirements. Implementing real-time processes as partial-solution tasks is one technique that may be beneficial. This type of task. when combined with intelligent control, has the potential for increasing pre-runtime schedulability, system maintainability. and runtime robustness. This research investigates the benefits of partial-solution tasks by experimentally measuring the …

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The Photo-Realistic Afit Virtual Cockpit, Milton E. Diaz Dec 1994

The Photo-Realistic Afit Virtual Cockpit, Milton E. Diaz

Theses and Dissertations

The Air Force Institute of Technology (AFIT) has pursued research in virtual environments since 1988. This research expands the current capabilities of the AFIT Virtual Cockpit (VC) by increasing the realism of the cockpit environment and improving the pilot's command interface. Realism is improved creating console elements from texture maps and polygonal models; these elements include working dials, switches and circuit breakers. The pilot command interface is improved in part by adapting the AFIT Information Pod using a two-dimensional mouse input to the virtual three-dimensional environment. This immersive virtual environment is also improved by modifications to the Head Mounted Display …

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Predicting Protein Structure Using Parallel Genetic Algorithms, George H. Gates Jr. Dec 1994

Predicting Protein Structure Using Parallel Genetic Algorithms, George H. Gates Jr.

Theses and Dissertations

The protein folding problem is a biochemistry Grand Challenge problem. The challenge is to reliably predict natural three-dimensional structures of polypeptides. Genetic algorithms (GAs) are robust, semi-optimal search techniques modeling natural evolutionary processes. Fast messy GAs (fmGAs) are variants of messy GAs that reduce the exponential time complexity to polynomial. This investigation evaluates the merits of parallel SGAs and fmGAs for minimizing the potential energy of a pentapeptide, (Met)-enkephalin. AFIT's energy model is compared to a similar model in a commercial package called QUANTA. Differences between the two models are identified and resolved to enhance GAs' abilities to correctly fold …

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Enhanced Visual User Interface Support For Domain-Oriented Application Composition Systems, Richard A. Guinto Dec 1994

Enhanced Visual User Interface Support For Domain-Oriented Application Composition Systems, Richard A. Guinto

Theses and Dissertations

This research refined the functionality and usability of a previously developed visual interface for a domain-oriented application composition system. The refinements incorporated more sophisticated user interface design concepts1 to reduce user workload. User workload was reduced through window reordering, menu redesign, and Human Computer Interaction techniques such as; combining repetitive procedures into single commands, reusing composition information whenever possible and deriving new information from existing information. The Software Refinery environment, including its visual interface tool INTERVISTA, was used to develop techniques for visualizing and manipulating objects contained in a formal knowledge base of objects. The interface was formally validated with …

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Design And Implementation Of Tools To Increase User Control And Knowledge Elicitation In A Virtual Battlespace, Jim J. Rohrer Nov 1994

Design And Implementation Of Tools To Increase User Control And Knowledge Elicitation In A Virtual Battlespace, Jim J. Rohrer

Theses and Dissertations

AFIT's Synthetic BattleBridge is an immersive command observatory for viewing large-area activity within a virtual environment. Three basic areas for improvement are addressed: (1) an improved, immersive, user interface, (2) direct control of atmospheric effects, and (3) improved knowledge elicitation by means of remote viewers, a new space scope, and an enhanced RADAR scope. These requirements are analyzed and implemented. Some functionality was lost but the results show a general improvement of environmental control and knowledge elicitation.

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Experiment Using Infrared Spectroscopy To Study The Effect Of Soil Characteristics Upon The Rate Of Trichloroethylene Desorption, Benjamin T. Kindt Sep 1994

Experiment Using Infrared Spectroscopy To Study The Effect Of Soil Characteristics Upon The Rate Of Trichloroethylene Desorption, Benjamin T. Kindt

Theses and Dissertations

This research investigated the influence of soil characteristics on the desorption of trichloroethylene (TCE). TCE is one of the most common contaminants at Superfund sites. Unfortunately, extraction of TCE from contaminated soils has been hindered by its slow and poorly understood desorption from soil particles. The rate and progress of desorption of TCE from seven types of soil with varying particle diameters and elemental compositions was measured using optical absorption techniques. Fitting the data to the Langmuir Isotherm functional form predicted in the literature yielded parameters for the desorption rate and total amount desorption each soil type. These parameters were …

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Modeling Trihalomethane Formation Potential From Wastewater Chlorination, Carol A. Mccormick Sep 1994

Modeling Trihalomethane Formation Potential From Wastewater Chlorination, Carol A. Mccormick

Theses and Dissertations

The deletion of federally mandated fecal coliform limits has led many states to review and modify their wastewater disinfection requirements. One issue in analyzing wastewater disinfection is the discharge of potentially carcinogenic halogenated organics formed during the chlorination process. This research investigates the formation of one class of the halogenated organics, the trihalomethanes. The applicability of using drinking water trihalomethane formation models for use with wastewater effluent is examined. Three models are compared for predictive capability by using measured trihalomethane values from previous research data. The results show that a previously developed model is applicable for use based on assumptions …

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A Numerical Analysis Of Smoothed Particle Hydrodynamics, David A. Fulk Sep 1994

A Numerical Analysis Of Smoothed Particle Hydrodynamics, David A. Fulk

Theses and Dissertations

This dissertation studies the numerical method of Smoothed Particle Hydrodynamics SPH as a technique for solving systems of conservation equations. The research starts with a detailed consistency analysis of the method. Higher dimensions and non-smooth functions are considered in addition to the smooth one dimensional case. A stability analysis is then performed. Using a linear technique, an instability is found. Solutions are proposed to resolve the instability. Also a total variation stability analysis is performed leading to a monotone form of SPH. The concepts of consistency and stability are then used in a convergence proof. This proof uses lemmas derived …

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Optimal Pulsed Pumping For Aquifer Remediation When Contaminant Transport Is Affected By Rate-Limited Sorption: A Calculus Of Variation Approach, Richard T. Hartman Sep 1994

Optimal Pulsed Pumping For Aquifer Remediation When Contaminant Transport Is Affected By Rate-Limited Sorption: A Calculus Of Variation Approach, Richard T. Hartman

Theses and Dissertations

The remediation of groundwater contamination continues to persist as a social and economic problem due to increased governmental regulations and public health concerns. Additionally, the geochemistry of the aquifer and the contaminant transport within the aquifer complicates the remediation process to restore contaminated aquifers to conditions compatible with health-based standards. Currently, the preferred method for aquifer cleanup pump-and-treat has several limitations including, the persistence of sorbed chemicals on soil matrix and the long term operation and maintenance expense. The impetus of this research was to demonstrate that a calculus of variations approach could be applied to a pulsed pumping aquifer …

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Mitigating The Effects Of Manpower Reductions At A Central Issue Facility By Improving The Allocation Of Servers: A Simulation Study, Michael K. Garrity, Christopher J. Wicker Sep 1994

Mitigating The Effects Of Manpower Reductions At A Central Issue Facility By Improving The Allocation Of Servers: A Simulation Study, Michael K. Garrity, Christopher J. Wicker

Theses and Dissertations

The purpose of this research was to determine a preferred server allocation and a preferred customer batch size for processing customers at an Army Central Issue Facility CIF under various manpower levels. The CIF is a retail warehouse which issues tactical clothing and equipment to individual soldiers. It is facing potential manpower reductions from the current level of 19 servers. The CIF exhibits flow shop characteristics. An assembly line balancing approach was used with the objective of reducing the customers average time-in-system. Five server allocation heuristics and three customer batch sizes were examined. The evaluation tool was a computer simulation …

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An Analysis Of The Effects Of Lean Logistics On The Current Air Force Reparable Pipeline: A Simulation Study, Tracey L. Hill, William N. Walker Sep 1994

An Analysis Of The Effects Of Lean Logistics On The Current Air Force Reparable Pipeline: A Simulation Study, Tracey L. Hill, William N. Walker

Theses and Dissertations

This research investigates the effect of Lean Logistics proposals on the current Air Force repairables pipeline. Lean Logistics proposes reducing reparable asset levels at operating bases, reducing transportation time between bases and depots, and reducing depot repair times. Computer simulation is used as a tool to perform a 3X3X3 full factorial experiment to determine the effects of the Lean Logistics proposals on fully mission capable aircraft and transportation cost. Results indicate that lean Logistics outperforms the current repairables pipeline in term of fully mission capable aircraft. A cost benefit analysis is performed to determine the trade offs between transportation costs …

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Analysis Of The Effects Of Fixed Costs On Learning Curve Calculations, Charles B. Shea, Kenneth P. Thomson Sep 1994

Analysis Of The Effects Of Fixed Costs On Learning Curve Calculations, Charles B. Shea, Kenneth P. Thomson

Theses and Dissertations

The goal of this research was to analyze the effect of fixed costs on learning curve calculations. The research focused on two general research areas. The first area addressed the identification of current cost analysis practice for handling fixed costs in learning curve calculations. After identification of current practice, the unit learning curve models AXb ability to estimate total production run costs for a new production run when the slope was derived from both total cost and variable cost historical lot data was examined. Historical lot cost data was simulated for both the total cost and variable cost cases under …

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High Resolution Fourier Transform Spectroscopy Of The First Overtone Of The N-O Stretch In Nitrosyl Bromide, Todd E. Wiest Sep 1994

High Resolution Fourier Transform Spectroscopy Of The First Overtone Of The N-O Stretch In Nitrosyl Bromide, Todd E. Wiest

Theses and Dissertations

Infrared Fourier transform spectroscopy of the first overtone of the nitric oxide (NO) bond stretch in nitrosyl bromide (ONBr) has been performed at a resolution of 0.02cm-1 to obtain the rotational parameters of the V1 = 2 energy level. Roughly 1000 transitions have been observed for rotational levels up to J = 80 and Ka = 7. The calculation of the complete set of rotational energy levels of this asymmetric molecule requires the numerical diagonalization of four, tridiagonal matricies for each J. From a non-linear least squares fit of observed transitions with J ≤ 40 using an …

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Development Of A Comprehensive Base-Level Environmental Training Program For Total Environmental Compliance, William M. Barrett Jr Sep 1994

Development Of A Comprehensive Base-Level Environmental Training Program For Total Environmental Compliance, William M. Barrett Jr

Theses and Dissertations

The leadership of the Air Force has established a goal of total environmental compliance because it is the right and necessary thing to do. Commitment to this goal can be accomplished through strong leadership, however, achieving this goal can only be accomplished through effective training. The lack of consistent guidance for developing and executing comprehensive base- level environmental training programs has forced bases to develop these training programs by whatever means available to them. This has resulted in a broad variation in the thoroughness of base-level training programs throughout the Air Force. This research effort investigates the relationship between the …

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