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Air Force Institute of Technology

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Visual Information Processing And Response Time In Traffic-Signal Cognition, Hasan H. Demirarslan Mar 1992

Visual Information Processing And Response Time In Traffic-Signal Cognition, Hasan H. Demirarslan

Theses and Dissertations

In man-machine design, it is important to quantify the reaction time components instead of simply determining the lump-sum reaction time to stimulus. The primary purpose of this thesis was to investigate the reaction time components, such as visual perception and muscle response time, and to quantify them by separating from their aggregated sum. The prime example, traffic-signal cognition simulation was used to examine human reaction time to signal change. With a modified computer program that stimulates the driver's approach to the intersection, we measured the subject's reaction times and examined behavioral patterns. Twelve subjects were involved in the experiment. A …

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An Investigation Of Modifications To The Tac Campaign Model, Efgan Denguer Mar 1992

An Investigation Of Modifications To The Tac Campaign Model, Efgan Denguer

Theses and Dissertations

This research investigates the cost and budget modifications to Mixmaster which is an aggregate version of the Theater Attack Model (TAM). Seven simple cost employment methods, a goal programming approach, a probabilistic approach for determining cost coefficients, and goal programming version of that probabilistic approach were applied to Mixmaster. Also, Mixmaster was enhanced with an additional leading constraint to incorporate the Air Force tactical considerations in a campaign scenario. The results favor the advantages of the goal programming approaches. In addition, the probabilistic approach introducing the time factor in the computations promises more accurate results, given that the required parameters …

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Automating The Weekly Flight Scheduling Process At The Usaf Test Pilot School, Gary G. Foster Mar 1992

Automating The Weekly Flight Scheduling Process At The Usaf Test Pilot School, Gary G. Foster

Theses and Dissertations

This study investigated different scheduling solution approaches that could be automated and applied at the USAF Test Pilot School (TPS). Currently at the TPS, flight schedules are manually developed on a daily basis. Weekly flight schedules are not developed due to the large quantity of data that must be processed to develop a flight schedule for an entire week. A weekly flight scheduling approach would reduce the occurrence of scheduling problems and unbalanced resource utilization, both of which are often the result of a daily flight scheduling approach. In addition, posting a flight schedule for the entire week would improve …

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Modular Simulation Of Hei Fragments And Blast Pressure, Gordon L. Galloway Mar 1992

Modular Simulation Of Hei Fragments And Blast Pressure, Gordon L. Galloway

Theses and Dissertations

The fragmentation and blast pressure of High Explosive Incendiary projectiles are major causes of aircraft fuel fires. Because Halon 1301 is being banned from DoD use as a fire suppressant, alternative fire suppressants must be developed and tested. These new suppressants must counteract the fire directly or eliminate one or more of the factors which cause the fire. To this end, this thesis takes a detailed look at the HEI processes that lead to a fire. A comprehensive review of the current knowledge and understanding of these processes is presented. In addition, hypothesized dependencies between the various processes are stated. …

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Causal Univariate Spatial-Temporal Autoregressive Moving Averages (Starma) Modelling Of Target Information To Generate Tasking Of A World-Wide Sensor System, Kelly A. Greene Mar 1992

Causal Univariate Spatial-Temporal Autoregressive Moving Averages (Starma) Modelling Of Target Information To Generate Tasking Of A World-Wide Sensor System, Kelly A. Greene

Theses and Dissertations

The Department of Defense employs a resource limited world-wide sensor system to detect certain events of interest. The purpose of this research was to establish a methodology using a univariate causal STARMA model for forecasting the relative probability of an event occurring in a geographical location during a time block of the day. These relative probabilities are used as input for a tasking model that assigns the scarce sensor resources so as to optimize the detection of these events. The STARMA model is appropriate for forecasting the relative probabilities because a definite temporal relationship and a definite spatial relationship exists …

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Developing Cmmca Flight Profiles For Cruise Missile Tracking, Andrew C. Hachman Mar 1992

Developing Cmmca Flight Profiles For Cruise Missile Tracking, Andrew C. Hachman

Theses and Dissertations

The Air Force has recently acquired two aircraft dedicated for cruise missile tracking. These aircraft, known as the Cruise Missile Mission Control Aircraft (CMMCA), are responsible for collecting data from the missile and United States. Due to tracking and positively controlling the missile during live fire testing over the western the limited tracking radar range and the flight characteristics of the CMMCA, tracking cruise missiles through complex maneuvers is not always possible. A FORTRAN optimization, based on flight simulation and optimal control theory, was written in a prior thesis effort in order to determine optimal CMMCA flight profiles for tracking …

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Optimization Of Stochastic Response Surfaces Subject To Constraints With Linear Programming, Robert G. Harvey Mar 1992

Optimization Of Stochastic Response Surfaces Subject To Constraints With Linear Programming, Robert G. Harvey

Theses and Dissertations

This research investigated an alternative to the traditional approaches of optimizing a stochastic response surface subject to constraints. This research investigated the bias in the expected value of the solution, possible alternative decision variable settings, and a method to improve the solution. A three step process is presented to evaluate stochastic response surfaces subject to constraints. Step 1 is to use a traditional approach to estimate the response surface and a covariance matrix through regression. Step 2 samples the objective function of the linear program (i.e., response surface) and identifies the extreme points visited. Step 3 presents a method to …

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Confidence Interval Estimation For Output Of Discrete-Event Simulations Using The Kalman Filter, Randall B. Howard Mar 1992

Confidence Interval Estimation For Output Of Discrete-Event Simulations Using The Kalman Filter, Randall B. Howard

Theses and Dissertations

Discrete-event simulation is computer modeling of stochastic, dynamic systems. The Kalman filter is a Bayesian stochastic estimation algorithm. Because of the correlated nature of simulation output, it is difficult to apply the methods of classical statistics directly when constructing confidence intervals of discrete-event simulation parameters. Through the determination of a dynamics equation and application of the Kalman filter to simulation output data, three new confidence interval construction techniques have been developed. One technique obtains an estimate of the mean value and its associated variance from an estimated Kalman filter. The second technique utilizes Multiple Model Adaptive Estimation (MMAE) techniques to …

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An Analysis Of Escort Formations, Mustafa Ilhan Mar 1992

An Analysis Of Escort Formations, Mustafa Ilhan

Theses and Dissertations

This study used computer simulation to investigate escort fighter formations unknown interceptor threat environment. A USAF computer simulation model, TAC, was used to simulate air combat between the escorts and the interceptors in several different combat scenarios. The escort formations were defined by the vertical and horizontal distances of the escort fighters from the main strike body. Interceptors were characterized as one of two types of fighters with dissimilar aircraft frames and missile firing ranges. A central composite design was used to mathematically model the effect of escort formations and interceptor type on the survivability of the bombers and escorts. …

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An A Priori Multiobjective Optimization Model Of A Search And Rescue Network, Joseph C. Imsand Jr. Mar 1992

An A Priori Multiobjective Optimization Model Of A Search And Rescue Network, Joseph C. Imsand Jr.

Theses and Dissertations

The purpose of this study was to determine the most robust frequency assignment for a search and rescue network. The focus was to assign weights to the transmitter areas of the network to determine which weight sequence produced the most robust frequency assignment. The DoD furnished weight sequences for twelve two-hour time blocks. These weight sequences were compared to a weight sequence with all weights having equal value. Network and linear programming were used to-solve this problem and generate frequency assignments for all weight sequences. Classical and tolerance sensitivity analysis were used to analyze the frequency assignments generated by the …

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Effects Of Facility Configurations And Scheduling Techniques On Aircraft Throughput For Warner Robins Alc Paint/Depaint Facilities, David V. Mcelveen Mar 1992

Effects Of Facility Configurations And Scheduling Techniques On Aircraft Throughput For Warner Robins Alc Paint/Depaint Facilities, David V. Mcelveen

Theses and Dissertations

The purpose of this research was to determine the effects of configuration options and dispatching rules on aircraft throughput for the WR- ALC paint/depaint facilities. A simulation model was constructed and used for this analysis as the primary means to conduct the research. The dispatching rules considered were first come first served, largest number in queue, shortest processing time, and a look ahead heuristic. Due to a reduction in the number of paint aircraft, no configuration option differing from the baseline significantly affected aircraft throughput. Dispatching rules were also found to produce no significant differences on aircraft throughput. Configuration options …

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An Outline For A Manufacturing Planning And Control System For A Repair/ Overhaul/Rebuilding Environment, Peter H. Miyares Mar 1992

An Outline For A Manufacturing Planning And Control System For A Repair/ Overhaul/Rebuilding Environment, Peter H. Miyares

Theses and Dissertations

This study outlines a structure for a manufacturing planning and control (MPC) system for a repair/overhaul/rebuilding environment. Included an examination of the organizational components that must be incorporated into the system and the planning functions for which the system can be used. The study compares and contrasts the differences between an MPC system for a maintenance organization and a manufacturing organization and concludes that the MPC system for a maintenance organization must account for the greater degree of variability that occurs within the process. The proposed system is composed of an information system which collects data from throughout an organization …

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Quantifying The Impact Of The Acquisition Professional Development Program Certification Requirements On The Air Force Institute Of Technology, Paul A. Nicholson Mar 1992

Quantifying The Impact Of The Acquisition Professional Development Program Certification Requirements On The Air Force Institute Of Technology, Paul A. Nicholson

Theses and Dissertations

The purpose of this research is to determine the impact of implementing the Acquisition Professional Development Program on the Air Force Institute of Technology. APDP is part of a DOD-wide effort to decrease inefficiency in the procurement process. The program encompasses a tri-level certification process based on experience, training, and educational standards. APDP serves as a guideline for professional development of acquisition personnel from entry to senior level management. Many of the courses required for certification are offered through AFIT School of Systems and Logistics. Integrating the new educational requirements as a standard for career development is expected to produce …

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A Sensitivity Analysis Of Circular Error Probable Approximation Techniques, Peter Puhek Mar 1992

A Sensitivity Analysis Of Circular Error Probable Approximation Techniques, Peter Puhek

Theses and Dissertations

Several algebraic CEP estimates models were examined in this study. Each assumes that the crossrange and downrange miss distances of the sample data follow a bivariate normal distribution. The analysis determined the sensitivities of these models to changes in the parameters of sample size, bias, correlation, and ellipticity. The accuracy of each model is expressed in terms of relative error, and the parameter regions in which a certain method dominated as the most accurate were noted. In general, it was found that bias was the most significant parameter in determining the best CEP method. A simple method, based on the …

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Spartan: An Instructional High Resolution Land Combat Model, David K. Cox Mar 1992

Spartan: An Instructional High Resolution Land Combat Model, David K. Cox

Theses and Dissertations

This project developed an instructional high resolution land combat simulation model. The purpose of this model is to demonstrate common techniques of modeling used in the present generation of US Army land combat models. This model is stochastic and uses an event scheduling type of discrete event time algorithm. The model represents a maximum of two six-man infantry squads in direct fire combat. The individual soldiers move, search for targets, engage targets, and react to hostile encounters. The data values provided will the model are all. generic and hypothetical. The model is only intended as a demonstration tool and has …

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An Improved Scheduling Algorithm For Eglin Afb Test Ranges, Jeffrey S. Antes Mar 1992

An Improved Scheduling Algorithm For Eglin Afb Test Ranges, Jeffrey S. Antes

Theses and Dissertations

This research develops an algorithm that integrates into an existing computerized scheduling system to improve the mission scheduling function for Eglin AFB test ranges. The primary objective of this research was to design an improved computerized scheduling aid. The measure of performance for this approach is the number of missions scheduled using this aid as compared to current Eglin capabilities. Constructive heuristics are used in the algorithm to schedule missions according to critical resource groups while ensuring mission priority is not violated. The success of this new interactive scheduling algorithm is measured against a schedule produced by the current computer …

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Gettysburg: An Analysis Of The Training Value Of Commercial Models, Jude C. Fernan Mar 1992

Gettysburg: An Analysis Of The Training Value Of Commercial Models, Jude C. Fernan

Theses and Dissertations

This study investigated the possibilities of using commercial combat models/war games dealing with the battle of Gettysburg as aids for the training of soldiers and leaders in the military. With the downsizing of the military and the high cost of training, there exists a need to reduce training costs while not affecting the quality of training. The military employs various military models to assist in training but has yet to fully tap the wealth of commercial combat models. One reason may be the lack of an investigative analysis into the soundness and applicability of commercial combat models to military training. …

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A Decision-Theoretic Approach To Recommending Action In The Air-To- Ground Aircraft Of The Future, Garrison H. Flemings Mar 1992

A Decision-Theoretic Approach To Recommending Action In The Air-To- Ground Aircraft Of The Future, Garrison H. Flemings

Theses and Dissertations

Designers of air-to-ground fighters of the future should consider including decision support systems to relieve pilots of some of the present workload. Those decision support systems should use utility theory. This work reviews two techniques of utility theory (decision trees and influence diagrams) and a new technique due to Morlan (probability ratio nets). The work includes a proposed structure for action recommendation systems in air-to-ground fighters of the future. The work describes an implementation of probability ratio nets. The work demonstrates the value of decision theory to air-to-ground fighters of the future by way of solving an example problem and …

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Saber: Airland Combat Training Model Credibility Assessment And Methodology, David L. Scagliola Mar 1992

Saber: Airland Combat Training Model Credibility Assessment And Methodology, David L. Scagliola

Theses and Dissertations

Saber is a theater-level, airland combat training model, designed by a number of computer science and engineering students and faculty at the Air Force Institute of Technology (AFIT). Saber is intended to replace the Agile model, which is currently used at the Air Force Wargaming Center, Maxwell AFB, Alabama for Theater Warfare Exercise (TWX) training purposes. This thesis focuses on the progress made towards generating the Saber training model, its ability to meet the objectives specified by the Wargaming Center, and its ability to represent actual combat. Specifically, this thesis is directed towards characterizing, establishing a credibility assessment, and developing …

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A Response Surface Methodology Study Of Ferroelectric Memory Devices, Kevin C. Smith Mar 1992

A Response Surface Methodology Study Of Ferroelectric Memory Devices, Kevin C. Smith

Theses and Dissertations

Fatigue in ferroelectric memory devices was studied. The application of fatigue pulses to a ferroelectric sample was controlled by the RT-66 Ferroelectric Tester, a variation of the Sawyer-Tower circuit. The RT-66 also controlled data collection following the fatiguing process. Seven variables were evaluated for their potential- affect on fatigue. A sequence of fatigue tests, which varied the settings of these variables, was developed using Response Surface Methodology (RSM) experimental designs. Least-squares regression models were developed once a particular RSM set of design experiments was completed. These models were evaluated using RSM tools, and the analysis of these models allowed the …

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A Study Of The Air Force Logistics Professional Development Model, David E. Gressman Mar 1992

A Study Of The Air Force Logistics Professional Development Model, David E. Gressman

Theses and Dissertations

The personnel population in the field of logistics has two major divisions. The first, is to organizations providing logistic support for the Air Force mission and is the Operations and maintenance area. The second area is Acquisition, which supports the Air Force mission to acquire new weapon systems. Until recently, there was no clear plan for logisticians assigned in these two major divisions to enhance their educational development. This research project reviewed several logistic career enhancement programs focusing on two new programs, the Acquisition Professional Development Program (APDP) and the Logistics Professional Development Program (LOGPDP). The APDP program has received …

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Development Of A Stratified Plate Model For Composite Panels, Alan L. Lesmerises Mar 1992

Development Of A Stratified Plate Model For Composite Panels, Alan L. Lesmerises

Theses and Dissertations

A new model for composites represents a composite panel as an alternating stack of isotropic matrix and orthotropic fiber-dominated layers. An energy approach results in a set of partial differential equations and boundary conditions where the mechanical properties of the matrix and fibers appear separately. Two solution methods are developed. The first, called Strata Theory is developed for general applications, while the second, called the Exact Stratified Plate, is used as a benchmark for comparison to Strata Theory. Both solutions assume zero gradients of displacement through the thickness of a fiber layer. They are compared for an isotropic material and …

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Boolean Reasoning And Informed Search In The Minimization Of Logic Circuits, James J. Kainec Mar 1992

Boolean Reasoning And Informed Search In The Minimization Of Logic Circuits, James J. Kainec

Theses and Dissertations

The minimization of logic circuits has been an important area of research for more than a half century. The approaches taken in this field, however, have for the most part been ad hoc. Boolean techniques have been employed to manipulate formulas, but not to perform symbolic reasoning. Boolean equations are employed principally as icons; they are never solved. The first objective of this dissertation is to apply Boolean reasoning systematically and uniformly to the minimization problem. Boolean reasoning entails the reduction of systems of Boolean equations to a single equation; the single equation is an abstraction, independent of the form …

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Experimental Feedback Of Fractional Order States Of A Lightly Damped Structure, Robert C. Mccall Mar 1992

Experimental Feedback Of Fractional Order States Of A Lightly Damped Structure, Robert C. Mccall

Theses and Dissertations

The purpose of this study was to investigate the effectiveness of using fractional order time derivatives of position feedback signals in the active control of vibration. To that end, circuitry was built and evaluated that finds the half order derivative of an input signal. The magnitude responses of the fractional derivative circuits is very good, but there are large phase shifts present that may degrade the performance of the controllers. Two methods of incorporating the fractional derivative signals into the controller were examined. One method involved developing a similarity transformation that transforms an integer order state controller into an equivalent …

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Hardware-Verification Through Logic Extraction, Michael A. Dukes Mar 1992

Hardware-Verification Through Logic Extraction, Michael A. Dukes

Theses and Dissertations

A Prolog-based system is described which employs logic-extraction to perform hardware-verification. The extraction rules are built automatically from hierarchical structural VHDL models, enabling the equivalence of a structural VHDL description and a layout specification to be verified. Pin-to-pin critical- path analysis is performed within the logic-extraction process; many noncritical paths are pruned early, making pin-to-pin critical path analysis of large circuits feasible. It is demonstrated that a design methodology based on logic extraction, VHDL, and a layout tool can provide a fabricated functionally- correct IC design without circuit-level or switch-level simulation. This methodology is shown to be practical for VLSI …

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A Computer Based Educational Aid For The Instruction Of Combat Modeling, Richard S. Moore Feb 1992

A Computer Based Educational Aid For The Instruction Of Combat Modeling, Richard S. Moore

Theses and Dissertations

The Air Force Institute of Technology is one of few institutions that teaches combat modeling. Combat models are typically dynamic computer simulations of specialized dynamic processes. Great difficulty exists in portraying these dynamic and recurrent processes with conventional static diagrams. This thesis produced a computer-based instructional aid which presents animated examples of processes common to combat models, demonstrates a simple few-on-few aerial combat model, and encourages student exploration and interaction with these presentations. This aid provides dynamic examples of random number generation, detection processes, target selection, and target destruction. A complete combat model demonstrating a few-on-few air duel is animated …

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An Examination Of Wing Rock For The F-15, Michael T. Davison Feb 1992

An Examination Of Wing Rock For The F-15, Michael T. Davison

Theses and Dissertations

Wing rock in the F-15 was examined both analytically and experimentally. Using a previously developed model for the F-15, bifurcation analysis and continuation techniques were used to map out the periodic wing rock solutions and the equilibrium solutions leading up to wing rock. this was done for four maneuvers; a 1 g stall, rudder sweeps, constant bank turns and a symmetric pullup. To supplement this research, time history simulations were used to examine. the time history of wing rock. A study of stability derivatives was also done, to determine the critical parameters in wing rock. Bifurcation was also used to …

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Distributed Ray Casting For High-Speed Volume Rendering, Patricia L. Brightbill Jan 1992

Distributed Ray Casting For High-Speed Volume Rendering, Patricia L. Brightbill

Theses and Dissertations

The volume rendering technique known as ray casting or ray tracing is notoriously slow for large volume sizes, yet provides superior images. A technique is needed to accelerate ray tracing volumes without depending on special purpose or parallel computers. The realization and improvements in distributed computing over the past two decades has motivated its use in this work. This thesis explores a technique to speedup ray casting by distributed programming. The work investigates the possibility of dividing the volume among general purpose workstations and casting rays (using Levoy's front-to-back algorithm) through each subvolume independently. The final step being the composition …

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Method For Gaseous Component Indentification With #3 Polymeric Film, Edward S. Kolesar Jr. Dec 1991

Method For Gaseous Component Indentification With #3 Polymeric Film, Edward S. Kolesar Jr.

AFIT Patents

A sensor having an interdigitated gate electrode field effect transistor (IGEFET) coupled to an electron beam evaporated copper phthalocyanine thin film is used to selectively detect parts-per-billion concentration levels of atmosphere contaminants such as nitrogen dioxide (NO2) and diisopropyl methylphosphonate (DIMP). The sensor is excited with a voltage pulse, and its time- and frequency-domain response are examined. The envelopes of the magnitude of the normalized difference frequency spectrums reveal features which unambiguously distinguish the NO2 and DIMP exposures.

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Migrating A C-Based Cad Tool To An Object-Oriented Database/C++ Environment: Conversion Costs And Performance Analysis, Mark A. Roth, Timothy M. Jacobs Dec 1991

Migrating A C-Based Cad Tool To An Object-Oriented Database/C++ Environment: Conversion Costs And Performance Analysis, Mark A. Roth, Timothy M. Jacobs

AFIT Documents

his paper examines the potential of object-oriented databases to support complex design applications. To do this we migrated the Magic very large scale integrated (VLSI) circuit design tool written in the C language to a new environment in which Magic's existing file management code is replaced with a C++ language interface to the commercial object-oriented database management system (OODBMS) product Object Store. In our initial implementation we found the performance of this tool as implemented on the OODBMS to be marginally faster than the tool as currently implemented with a flat file system in several critical areas. Increased functionality, including …

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