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Sensitivity Analysis For The Selection Of Linear Quadratic Regulator Weighing Parameters Q And R For Active Vibration Suppression Of A Cantilevered Beam, Steven L. Story
Sensitivity Analysis For The Selection Of Linear Quadratic Regulator Weighing Parameters Q And R For Active Vibration Suppression Of A Cantilevered Beam, Steven L. Story
Theses and Dissertations
There has been much interest during the past decade to develop and launch large space structures. The high cost of launching material into orbit will require that these structures be assembled in space using light weight elements which are vulnerable to dynamic excitations. Active control may be necessary to rapidly attenuate large amplitude vibrations. The active vibration control system is usually designed after the structure has been optimized. The integrated design of the control system and the structure may provide additional weight savings. This thesis presents a sensitivity analysis of the structure/ control optimization problem. The structure used is an …
Transfer Of 4gl Application From Ingres To Oracle, Adnan Altunisik
Transfer Of 4gl Application From Ingres To Oracle, Adnan Altunisik
Theses and Dissertations
This paper documents the transfer of 4GL applications from INGRES to ORACLE. As a result of a fast and conceptual change in computer languages, 4GLs were developed and evolved. These are programming support tools whose goal is, basically, to make the programs more efficient by reducing the number of instructions. Both ORACLE and INGRES database systems use 4GLs to develop applications. Their 4GL environments and their facilities for application development are investigated and explained in depth in this effort. The TWX application, which was originally implemented in INGRES by using its 4GL, is designed and reimplemented in ORACLE. This is …
The Boundary Element Method Applied To The Two Dimensional Stefan Moving Boundary Problem, Donald C. Vosika
The Boundary Element Method Applied To The Two Dimensional Stefan Moving Boundary Problem, Donald C. Vosika
Theses and Dissertations
This thesis considers problems for which the boundary is not known before the problem is solved and must be determined as part of the solution. We consider a time dependent problem which results in a moving boundary. We look at the heat conduction/diffusion equation in one and two spatial dimensions. We use Green's Theorem to yield a Volterra boundary integral equation which involves an unknown function on the moving boundary. We use the boundary element method to obtain a solution. Graphical results for the two dimensional problem are presented.
A Common Interface Real-Time Multiprocessor Operating System For Embedded Systems, Michael S. Rottman
A Common Interface Real-Time Multiprocessor Operating System For Embedded Systems, Michael S. Rottman
Theses and Dissertations
Large real time applications such as aerospace avionics systems, battle management, and factory automation place many demands and constraints on the computing system not found in other applications. Software development is hindered by software dependence on the computer architecture and the lack of portability between systems. This thesis specifies and designs a real time multiprocessor operating system (RTMOS) that implements a consistent programming model, enabling the development of real time parallel software independent of the target architecture. The RTMOS defines the core functionality required to demonstrate the programming model. The RTMOS functional requirements are specified using Structured Analysis and Design …
An Automated Red Player For The Theater Warfare Exercise, Karl W. Kabanek
An Automated Red Player For The Theater Warfare Exercise, Karl W. Kabanek
Theses and Dissertations
The Theater Warfare Exercise (TWX) is a two-sided, theater-level, decision-making exercise created, maintained and used by the personnel at the Air Force Wargaming Center. It is used to allow military officers to practice the decision-making process needed for the wartime employment of air power. An automated player was designed and a prototype implemented for the red (enemy) player using an expert system shell. The automated red player uses the TWX database that contains the data on the different units used in exercise. From the data the automated red player builds mission packages for the various types of missions required in …
Optimal Iterative Task Scheduling For Parallel Simulations, Joann M. Sartor
Optimal Iterative Task Scheduling For Parallel Simulations, Joann M. Sartor
Theses and Dissertations
The ultimate purpose of this research is to reduce the time needed for execution of parallel computer simulations. In particular, the impact of task assignment strategies is determined for parallel VHDL circuit simulations. The classical scheduling problem, which assigns n precedence-constrained tasks to m processors is NP-complete in all but the simplest cases. The problem of assigning simulation tasks is further complicated by the iterative nature of computer simulations: each task is required to execute multiple times as the simulation executes. This investigation develops a polynomial-time algorithm (the level strategy) which provides optimal assignment for iterative systems with specific constraints. …
A Computer Simulation Of Braitenberg Vehicles, Eric B. Werkowitz
A Computer Simulation Of Braitenberg Vehicles, Eric B. Werkowitz
Theses and Dissertations
In his treatise, Vehicles: Experiments in Synthetic Psychology, Valentino Braitenberg used simple, autonomous vehicle designs to illustrate the principles behind animal nervous system organization and operation. The goal of this effort was to produce a computer program to allow a researcher to experiment with these concepts and to analyze their performance using methods employed by experimental psychologists. The resulting program allows the user to design vehicles that respond to changes in their environments and that have the ability to adapt their behavior, using a learning algorithm developed by Teuvo Kohonen. The vehicle designer is free to select sensor attributes, …
A Fully Coupled, Automated Formation Control System For Dissimilar Aircraft In Maneuvering Formation Flight, Paul R. Rohs
A Fully Coupled, Automated Formation Control System For Dissimilar Aircraft In Maneuvering Formation Flight, Paul R. Rohs
Theses and Dissertations
This study developed a fully automated formulation control system, capable of controlling a number of like or dissimilar aircraft in maneuvering formation flight. C-130 fixed wing aircraft and H-53 helicopters were modelled in various formulations and simulated through a mix of maneuvers. External formation guidance was assumed as a single data burst of nominal function guidance commands and separation distances for each wing aircraft in the formation. No communication was assumed between formation aircraft. Wing aircraft track lead aircraft maneuvering with an ideal on-board sensor, maneuvering to maintain relative position. It was determined that lead aircraft inputs must be attenuated …
Investigation Of A Zero-One Integer Programming Approach To Automating The Scheduling Process At The Usaf Test Pilot School, Lisa M. Hassel
Investigation Of A Zero-One Integer Programming Approach To Automating The Scheduling Process At The Usaf Test Pilot School, Lisa M. Hassel
Theses and Dissertations
This thesis investigated models that could be used to determine a feasible schedule for the Test Pilot School (TPS) training program and form the basis for an automated scheduling system. The TPS problem is formulated as a 0-1 integer linear program and is solved using preprocessing techniques and the Branch-and-Bound algorithm. The method produced feasible solutions for small problems that equate to portions of the TPS schedule but cannot efficiently solve large problems like the full TPS problem. More investigation should be conducted to alter the method developed in the study so it could be used for large problems. A …
Saber: A Theater Level Wargame, William F. Mann Iii
Saber: A Theater Level Wargame, William F. Mann Iii
Theses and Dissertations
This thesis provides a foundation to build a new theater level computerized wargame for the Air Force Wargaming Center, Maxwell AFB, AL to replace the Theater War Exercise (TWX), also known as Agile. Given a recently developed land battle, this thesis' effort links US Air Force doctrine with a conceptual model's framework and designs a new air battle module. The integration of both the air and land battles forms a new game, Saber. This thesis redefines the ground combat units of the land battle, and adds theater air defense units, bases and aircraft packages. This thesis introduces stochastic attrition between …
The Modeling Of Employment Decisions For Peacetime Contingency Operations, Michael C. Wilmer
The Modeling Of Employment Decisions For Peacetime Contingency Operations, Michael C. Wilmer
Theses and Dissertations
This research provided the conceptualization of a model that can be used to aid the operations planner in choosing employment strategies for peacetime contingency operations. The model uses object-oriented design and is constructed in two levels. The top layer of the model is a decision analytic model which provides a framework within which to structure the employment decision. It enables the user to quantify the probabilities of random events and the preferences of the commander and determine how these factors influence the decision. A Game Theory model is used to determine the probabilities with which the Red commander will adopt …
The Utility Of Elliptical And Circular Confidence Regions For Hfdf Receivers, Paul T. Nemec
The Utility Of Elliptical And Circular Confidence Regions For Hfdf Receivers, Paul T. Nemec
Theses and Dissertations
This thesis investigates HFDF confidence region (CR) shape exhibited by geolocations in a search-and-rescue context. In Phase I, a Keeney-Raiffa multiattribute utility function was developed which allowed an analytical measure of preference between elliptical and equivalent- probability circular CRs. Phase II utilized a likelihood approach to establish CR shape for sample operational geolocations having multiple points of bearing intersections. For 12 sample Phase I geolocations, the elliptical CR always had higher utility than its corresponding circular CR. For accepted sample geolocations, a preference condition was developed whereby a circular CR would only be preferred over the corresponding elliptical CR if …
Enhancements To Pcrsm, Laurie M. Rouillard
Enhancements To Pcrsm, Laurie M. Rouillard
Theses and Dissertations
The purpose of this study was to enhance the capability of PCRSM, a personal computer based decisions support system, to perform response surface methodology. PCRSM was enhanced to allow the printing of graphical displays such as residual plots and to provide the capability to decode the regression equation back to the original variables. Reverse documentation of the prototype was also developed to describe the interfacing of the individual executable modules and development environment. Response surface methodology is a group of statistical tools used to analyze the relationships between predictors (input variables) and responses (output variables).
Locating Direction Finders In A Generalized Search And Rescue Network, Jean M. Steppe
Locating Direction Finders In A Generalized Search And Rescue Network, Jean M. Steppe
Theses and Dissertations
A multiobjective linear programming approach is applied to the problem of locating receiving stations and HFDF receivers in a search and rescue network in order to maximize the expected number of distress signals that are geolocated. The multiobjective formulation is made up of two contrasting objectives: one maximizes the expected accurate lines of bearing, and one minimizes the excess coverage in the network. The individual objectives are weighted and combined into a composite objective function. The resulting problem is expressed as a two-stage network flow problem and is solved using SAS LP with a limited number of binary variables. The …
An Interactive Life Cycle Cost Forecasting Tool, John A. Gibson Iv
An Interactive Life Cycle Cost Forecasting Tool, John A. Gibson Iv
Theses and Dissertations
Enhancements were applied to an existing tool designed to estimate life cycle costs. These enhancements provide greater ease of data manipulation, additional options in developing models, and the ability to make modifications to suit the needs of the user. Life cycle costs can be generated quickly and easily. Analysis proved the amount of work done by the computer could be reduced with no loss of information. Additionally, the paths available to the user are shown graphically through flow charts--aiding in the learning process. The efforts of the user can now be directed towards developing models instead of spending those efforts …
A Study Of Variables To Help Predict Navigator Training Success And Classification, Gary A. Hagler
A Study Of Variables To Help Predict Navigator Training Success And Classification, Gary A. Hagler
Theses and Dissertations
This study attempted to build statistical models which could possibly be used to help predict an individual's final outcome of pass or fail from Undergraduate Navigator Training (UNT). Also, the research tried to develop models to help place a potential trainee into one of the three training tracks at UNT. The variables studied were test scores from a computerized testing device which measured psychomotor and cognitive skills of individuals entering training. The Air Force Officers Qualifying Test (AFOQT) scores were also variables considered. Data was from 317 trainees from the years 1988 to 1990. Discriminant analysis was applied in an …
Hardware Upgrade Of A Segmented Drum Assay System, Claude A. Irvine
Hardware Upgrade Of A Segmented Drum Assay System, Claude A. Irvine
Theses and Dissertations
This paper describes the conversion of a DEC PDP-11/05 computer system, previously used in Canberra's Model 2220B segmented gamma scanner, with an IBM PC. Two tasks necessary for completion of the project involved reestablishing communications with a Canberra Series 35+ multi-channel analyzer and a scan table controller. An additional serial/parallel card was installed in the PC to reinstate comunications with the multi-channel analyzer. For computer control of scan table controller operations a digital input/output card was used along with an external electromechanical relay board; when implemented together this hardware setup replaces functions that were normally processed through a motion control …
A Study Of The Liquid-Solid Interface During Rapid Resolidification Of Cooper-Titanium Using Molecular Dynamics, Craig L. Loisel
A Study Of The Liquid-Solid Interface During Rapid Resolidification Of Cooper-Titanium Using Molecular Dynamics, Craig L. Loisel
Theses and Dissertations
The behavior of the liquid-solid interface during resolidification of a condensed copper-titanium crystal is studied by atomistic simulation. A system of 1080 atoms (540 of each type) was simulated. The interface was created using monte carlo techniques and resolidification was performed by molecular dynamics. Resolidification was attempted at temperatures of 1200 K, 1100 K, 1000 K, 900 K, 818 K and 773 K. The liquid-solid interface was found to move only at 773 K, resulting in a chemically disordered crystal. The interface velocity observed in the simulation is 6.6 m/s which agrees well with the theoretical value of 5.5 m/ …
High Altitude Neutral Particle Transport Using The Monte Carlo Simulation Code Mcnp With Variable Density Atmosphere, David L. Monti
High Altitude Neutral Particle Transport Using The Monte Carlo Simulation Code Mcnp With Variable Density Atmosphere, David L. Monti
Theses and Dissertations
The Monte Carlo transport code, MCNP was modified for purposes of two dimensional neutron-photon transport modelling in a variable density atmosphere. Calculations were performed using cylindrical (r, z) geometry and a point isotropic neutron-photon source at an elevation of 40 kilometers. Neutron and photon fluence results were computed using ring detectors for field points at constant range versus source elevation angle and for field points at constant altitude versus radius. Comparisons between the modified and unmodified versions of MCNP showed a decrease in run time by a factor of two was possible. Only a fraction of the spatial cells previously …
New Modified Anderson-Darling And Cramer-Von Mises Goodness-Of-Fit Tests For A Normal Distribution With Specified Parameters, Goksel Kahya
New Modified Anderson-Darling And Cramer-Von Mises Goodness-Of-Fit Tests For A Normal Distribution With Specified Parameters, Goksel Kahya
Theses and Dissertations
This thesis improves the powers of the Anderson-Darling and Cramer-von Mises goodness-of-fit tests using the mean rank and the median rank plotting positions. A Monte Carlo simulation of 5000 repetitions is used to generate the critical values from n =4 through n =80 for certain significance levels. An extensive power study is performed to compare the powers of the modified tests to the known tests for the uniform, the exponential, the double exponential, the lognormal, and the Weibull distributions. The power of the A-D tests modified by the median rank plotting and the mean rank plotting position are approximately 0.01% …
Mapping Efficient Numerical Methods To The Solution Of Multiple Objective Linear Programs, Michael A. Shields
Mapping Efficient Numerical Methods To The Solution Of Multiple Objective Linear Programs, Michael A. Shields
Theses and Dissertations
This investigation was initiated to increase the speed, accuracy and capacity of m-simplex algorithms for solving multiple objective linear programming problems. Specifically, improvements were sought through the application of general numerical techniques. It soon became apparent that the m- simplex algorithm, like the simplex algorithm, is heavily dependent upon the technology of solving related systems of linear equations. The numerical arguments for the application of LU triangular matrix factorization techniques to simplex computations are well known. OF special significance to m-simplex performance is the case of rank-k updates to basis factorizations. A stable and efficient LU approach to the rank-k …
A Goodness-Of-Fit Test For A Family Of Two Parameter Weibulls With Known Shape Using Minimum Distance Estimation Of Parameters, John S. Crown
A Goodness-Of-Fit Test For A Family Of Two Parameter Weibulls With Known Shape Using Minimum Distance Estimation Of Parameters, John S. Crown
Theses and Dissertations
This research is to produce a modified Anderson-Darling goodness of fit test for the Weibull distribution when the location parameter is found by minimum distance estimation, the shape parameter is assumed known, and the MLE is used for the scale parameter. The critical values for the Anderson-Darling test are generated via Monte Carlo simulation when both the Anderson-Darling and Cramer-Von Mises distance statistics are minimized. These critical values are then used for a power study. The Monte Carlo simulation used 5000 repetitions for sample sizes of 5,8,12,15,16,20 and 25 with the Weibull shape parameter of . 5(.5)4.0. The power study …
Location And Routing Of The Defense Courier Service Aerial Network, Steven F. Baker
Location And Routing Of The Defense Courier Service Aerial Network, Steven F. Baker
Theses and Dissertations
This study extends work done by the Military Airlift Command's Analysis Group on reducing the operating costs of the Defense Courier Service aerial network. The study's primary focus is to minimize those costs by varying the number and location of servicing depots, and the routes flown from those depots. The theoretical algorithm used in the methodology is an expansion of Laporte's (1986) formulation of the multiple depot multiple travelling salesmen facility-location problem. Multiple servicing frequency is addressed by clustering co-located demands with Kulkarni's (1985) subtour breaking constraint. Vehicle range is considered by redressing a shortfall of the subtour breaking constraint, …
Green's Function Approach To The Atmospheric Albedo Neutron Transport Problem, Donald R. Culp Jr.
Green's Function Approach To The Atmospheric Albedo Neutron Transport Problem, Donald R. Culp Jr.
Theses and Dissertations
This study investigated the reflection of neutron radiation off of the earth's upper atmosphere, with the goal of generating a quick-running computer algorithm to estimate the albedo free field flux at any point above the atmosphere. This thesis involved analytic development in the construction of the algorithm and employed Monte Carlo simulation for generating the energy and angle distributions of the reflected radiation. The Green's function approach to modeling the neutron transport process involved approximating each energy bin of the source spectrum as a Dirac pulse in energy and summing the contribution from each source bin. The computer program integrates …
The Optimal Location Of Geodss Sensors In Canada, Pierre J. Forgues
The Optimal Location Of Geodss Sensors In Canada, Pierre J. Forgues
Theses and Dissertations
This thesis studies the maximal coverage p-median and the set covering facility location problems as applied to the GEODSS location problem. The classical single-objective mathematical formulations of the p-median and set covering problems are converted into network-flow formulations and various solution methods are developed using a scaled-down version of the GEODSS problem. The next step is the introduction of a second criterion function into the problem. This second function consists of minimizing the sum of the variance in coverage at the selected locations. Research reveals the deficiencies of MOLP (multiobjective linear programming) techniques in generating the efficient frontier of an …
Three Degrees Of Freedom Compliant Motion Control For Robotic Aircraft Refueling, Clayton M. Andersen
Three Degrees Of Freedom Compliant Motion Control For Robotic Aircraft Refueling, Clayton M. Andersen
Theses and Dissertations
The Air Force Institute of Technology (AFIT) supports on-going research in application of robotic technology to enhance assembly tasks. As a testbed, AFIT supports the ground-based aerial refueling project, with an emphasis on visual servoing techniques and compliant motion control. This thesis focuses on compliant motion control. Previous research developed the testing environment, which includes a PUMA-560 industrial manipulator, and a half scale mock-up of an aerial refueling system. This effort corrected and expanded the existing two degree of freedom (DOF) compliant controller to three DOF. Three DOF compliance was demonstrated by inserting the refueling nozzle into the receiver port. …
Nonlinear Analysis Of A Spinning Symmetric Satellite In An Elliptical Orbit, Michael Ulisse
Nonlinear Analysis Of A Spinning Symmetric Satellite In An Elliptical Orbit, Michael Ulisse
Theses and Dissertations
Controlled and uncontrolled equations of motion for a spinning symmetric satellite in an elliptical orbit are analysed using Floquet theory, Poincare maps, and continuation. The equations of motion for the uncontrolled system are derived via energy methods. A simple feedback controller design and one based on Floquet theory are presented. Parameters varied in the equations of motion include the spin about the symmetry axis of the satellite, the inertia ratio of the satellite, the eccentricity of the orbit, and the controller gains. Floquet analyses determine local stability and bifurcation points. Poincare maps exhibit some interesting and complex structure in the …
Characterization Of Multilayer Perceptrons And Their Application To Multisensor Automatic Target Detection, Dennis W. Ruck
Characterization Of Multilayer Perceptrons And Their Application To Multisensor Automatic Target Detection, Dennis W. Ruck
Theses and Dissertations
The multilayer perceptron was extensively analyzed. A technique for analyzing the multilayer perceptron, the saliency measure, was developed which provides a measure of the importance of inputs. The method was compared to the conventional statistical technique of best features and shown to provide similar rankings of the input. Using the saliency measure, it is shown that the multilayer perceptron effectively ignores useless inputs and that whether it is trained using backpropagation or extended Kalman filtering, the weighting of the inputs is the same. The backpropagation training algorithm is shown to be a degenerate version of the extended Kalman filter. The …
Recursive Optimization Of Digital Circuits, John Knutson
Recursive Optimization Of Digital Circuits, John Knutson
Theses and Dissertations
The goal of this thesis is twofold: first, to identify the advantages and disadvantages of existing optimization systems and second, to develop an optimization system that uses Boolean principles to generate a recursive realization of combinational logic. Current multi-level optimization systems fall into two categories: local optimization which removes redundancy by pattern matching on a local scale and global optimization which works with the equations that specify a circuit rather than with the circuit implementation itself. While global systems are very flexible and can produce near-optimal solutions, they are inherently complex. This research effort demonstrates that an effective global optimization …
Automatic Determination Of Recommended Test Combinations For Ada Compilers, James S. Marr
Automatic Determination Of Recommended Test Combinations For Ada Compilers, James S. Marr
Theses and Dissertations
Ada compilers are validated using the Ada Compiler Validation Capability (ACVC) test suit, containing over 4000 individual test programs. Each test program focuses, to the extent possible, on a single language feature. Despite the advantages of this atomic testing methodology, it is often the unexpected interactions between language features that result in compilation problems. This research investigated techniques to automatically identify recommended combinations of Ada language features for compiler testing. A prototype program was developed to analyze the Ada language grammar specification and generate a list of recommended of features to be tested. The output from this program will be …