Engineering Commons^™

A Statistical Analysis Of Terrorism And Instability In Latin America, Juan A. Hurtado

Theses and Dissertations

In this research the effect of socioeconomic factors on terrorism and government instability in Latin America are studied. A commonly held opinion is that terrorism and instability are caused by repressive conditions. The objective of this research was to generate a methodology to forecast terrorism and instability given certain socioeconomic indicators. This methodology was generated for individual countries, two groups of countries, and a composite developing country. A set of 28 socioeconomic factors were evaluated and reduced based on correlation analysis. Patterns of terrorism and instability were investigated through data analysis and factor analysis. Multiple regression was used to develop …

A Monte Carlo Study Of The Raw And Normal Varimax Rotation Criterion In Factor Analysis, Willam M. Ibinson

Theses and Dissertations

Factor analysis is a multivariate statistical procedure for analyzing and reducing large data sets. Many factor analysis schemes and techniques are available that lead to strikingly different results from the same data. This research effort used a Monte Carlo approach to investigate the properties of two rotation methods for simple structure, Kaiser's raw and normal varimax criterion. Data sets were developed from a set of contrived experimental factor patterns by multiplying each factor pattern by its transpose to create a covariance matrix. Data sets of multivariate normal deviates were in turn generated from each covariance matrix via the Choleski algorithm. …

The Airlift Capabilities Estimation Prototype: A Case Study In Model Validation, Randy Mccanne

Theses and Dissertations

This study investigates the application of a life cycle approach to the validation of operational models. The classic waterfall life cycle from software engineering is adapted for use on mathematical models by defining four stages of model development. Each stage is discussed in detail and examples of the output from each stage are presented. In addition, techniques are investigated for applying the proposed life cycle to existing models through the recovery of life cycle stages. The methodology is applied to a linear programming model developed for planning airlift operations to demonstrate the power of the life cycle approach to validation. …

Including Maximum Sustained Wind Speed In A Time Series Model To Forecast Hurricane Movement, Timothy B. Mott

Theses and Dissertations

Techniques for applying time series fundamentals to forecasting hurricane movement are thoroughly examined in this research. The objectives are: (1) to modify Dr. Thomas Curry's threshold autoregressive time series model to improve its ability to forecast hurricane movement, (2) to forecast the maximum sustained wind speed for a hurricane, and (3) to identify if wind speed should be included as an explanatory variable to aid in forecasting hurricane movement. Eleven different models to predict the latitude, longitude and maximum sustained wind speed are compared and contrasted with Curry's bivariate time series model. The results showed the modifications allow significant forecasting …

A Modified Anderson Darling Goodness-Of-Fit Test For The Gamma Distribution With Unknown Scale And Location Parameters, Tamer Ozmen

Theses and Dissertations

A new modified Anderson-Darling goodness-of-fit test is introduced for the three-parameter Gamma distribution when the location parameter is found by minimum distance estimation and scale parameter by maximum likelihood estimation. Monte Carlo simulation studies were performed to calculate the critical values for A-D test when A-D statistic is minimized. These critical values are then used for testing whether a set of observations follows a Gamma distribution when the scale and location parameters axe unspecified and are estimated from the sample. Functional relationship between the critical values of A-D is also examined for each shape parameter by the variables, sample size …

Optimal Silo Attack Plan For The Red Integrated Strategic Offensive Plan (Risop), Richard C. Pace

Theses and Dissertations

The Joint Staff Directorate for Force Structure, Resources, and Assessment (J-8) sought a procedure which could be used to generate an optimal missile allocation for the silo attack portion of the Red Integrated Strategic Offensive Plan (RISOP). Their current solution procedure is a manual heuristic which is time-consuming and is not guaranteed to lead to an optimal solution. J- 8 defines an optimal solution as a feasible solution which minimizes both the flight time of the missile that impacts first and the duration of the attack. J- 8 defined several input rules which limit how missiles may be allocated. A …

Integrating Psychological Operations Into The Joint Theater Level Simulation (Jtls), C. Matthew Pecot Iii

Theses and Dissertations

This thesis provides a prototype and methodology for integrating psychological operations (PSYOP) into the Joint Theater Level Simulation (JTLS) combat model. The requirement rose out of the need for aggregate-level training models to reflect the role of PSYOP so that commanders and their staffs can learn how to manage plan for, and conduct PSYOP within the context of AirLand battle doctrine. As the JTLS model currently exists, there is no representation of psychological operations whatsoever. This thesis outlines a methodology for incorporating the PSYOP analysis process (including the target audience analysis), the PSYOP product development and production process, the PSYOP …

Bradley Fighting Vehicle Gunnery: An Analysis Of Engagement Strategies For The M242 25-Mm Automatic Gun, James G. Riley

Theses and Dissertations

This thesis studies various engagement strategies for the Bradley Fighting Vehicle's 25-mm automatic gun firing APDS-T ammunition against a BMP- type target. The Army currently provides only the broadest guidance for the structure of the 25-mm point target engagement which results in the employment of an assortment of strategies throughout the Bradley community. The goal of this research was to determine if a best method exists. Bradley gunnery is a complex set commander/gunner interactions which can be difficult to represent with the analytic models commonly found in the literature. A model, based on the simulation methods used by the US …

Determining Cargo Flow For Air Mobility Command's Channel Cargo System, Michael Del Rosario

Theses and Dissertations

This research investigated using a multiperiod multicommodity minimal cost flow (M2MCF) formulation to model the channel cargo system of the United States Air Force's Air Mobility Command (AMC). The objective of this research was to determine how cargo should flow in the channel cargo system in order to minimize the cargo's delay enroute from its origin to its destination. This research showed the size of an M2MCF model of the channel cargo system exceeds AMC's computational capabilities. Additionally, this research describes three approaches to reduce the problem size. Because of the problem size and other modeling limitations discovered during this …

Theater Airlifter Survivability On The Ground, Michael A. Silver

Theses and Dissertations

Airlifter attrition can severely decrease the throughput of cargo during extended airlift operations. Much work has been done to enhance the tactical airlifter survivability in the air but little study has gone into airlifter survivability on the ground. This thesis develops a method to measure the threat to parked aircraft from ground weapons. Specific scenarios cover airlifter mobility on the ground, time to off-load cargo, short-field takeoff capability and attack by infantry weapons. A weapon is examined at each of several firing ranges to target. The threat to the aircraft is measured as the probability that the aircraft is hit. …

A Generalized Simulation Model For A Typical Medical Treatment Facility Obstetrical Unit, Annette M. Stephens

Theses and Dissertations

The purpose of this research was to develop a decision support tool for users at Air Force Medical Treatment Facility obstetrical (OB) units. The immediate needs of the generalized simulation model contained in this research provide obstetrical wards with the capability to identify unit effectiveness as well as the ability to predict future performance. As a result of this model, decision-makers will now have access to information on system performance as well as insight into the effects of changing conditions. This model was formulated with the flexibility to be adapted to OB wards at regional and local hospitals throughout the …

A Comparison Of Variable Selection Criteria For Multiple Linear Regression: A Second Simulation Study, David P. Woollard

Theses and Dissertations

This thesis implements a variable selection method proposed by Alan J. Miller, and makes an extension of Ross J. Hansen's 1988 thesis research by comparing the methods he examined: Minimum MSE, Minimum Sp, and Minimum Cp with Miller's method. Response Surface methodology is employed with two performance measures: the percentage of correct variables in a model and the Theoretical Mean Squared Error of Prediction (TMSEP). Each technique is applied on generated data with known multicollinearities, variances, random predictors, and sample sizes. Both performance measures are computed for models selected under each technique. A full factorial design using each performance measure …

Modified Goodness-Of-Fit Tests For The Weibull Distribution, Erol Yucel

Theses and Dissertations

This research will produce a new modified Anderson-Darling and W* goodness of fit statistics for the three parameter Weibull Distribution when all parameters unknown and estimated by Maximum Likelihood-Minimum Distance combination. The critical values for each statistic, sample size and a levels 0. 20, 0.15, 0.10, 0.05 and 0.01 are produced. The Monte Carlo Simulation used 5000 repetitions for sample sizes of 10, 15, 20, 25, 30, 40, and 50 with the Weibull shape equals to 3, scale equals to 4 and location equals to 10. The power study is made for the same sizes as above with the hypothesized …

An Analysis Of The Generalized Lambda Distribution, Robert J. Bergevin

Theses and Dissertations

The Generalized Lambda Distribution (GLD) is a four parameter function that is capable of mimicking the behavior of a wide range of probability density functions (pdfs). Unfortunately, the GLD presently cannot model every possible type of pdf. Since the reasons for this limitation are unknown, this thesis examines several potential problems in an attempt to expand the range of distributions the GLD can mimic. We first present a discussion of the behavior of the algorithm that is used to search for the appropriate GLD parameter values. In particular, we examine the effect of using an unconstrained search to find the …

A New Goodness-Of-Fit Test For The Weibull Distribution Based On Spacings, Mark C. Coppa

Theses and Dissertations

The critical values for a new goodness-of-fit test based on spacings are generated for the Weibull distribution when the shape parameter is known. The critical values are used for testing whether a set of observations follow a Weibull distribution when the scale and location parameters are unknown. A Monte Carlo simulation with 10,000 iterations is used to generate the critical values for sample sizes 5(5)35 at shape parameters k equal to 0.5(0.5)1.5 and for sample sizes 5(5)20 at shape parameters k = 2.0(1.0)4.0. A Monte Carlo power study of the Z* test statistic using 5000 iterations is accomplished using nine …

An Analysis Of The Ability Of Commercial Wargames To Fulfill The Education Requirements Of The Air Force Wargaming Center, Scott Goehring

Theses and Dissertations

It has been the contention of some that current commercial wargames could possibly fulfill the education requirements addressed by the Air Force Wargaming Center. The Wargaming Center, lacking the opportunity to conduct a thorough, in-house analysis of these commercial wargames, requested an independent evaluation be performed. This thesis identifies potential commercial wargames and provides an analysis of those wargames to determine their ability to educate senior military officers in the application of aerospace power. In addition, this thesis establishes a set of Measures of Effectiveness (MOEs) against which future wargames can be easily evaluated. The MOEs were developed from the …

An Analysis Of Tactical Airlifter Characteristics And Their Impact On Theater Airlift System Performance, John J. Koger

Theses and Dissertations

This study used computer simulation and Response Surface Technology to determine what tactical airlifter characteristics most impact theater airlift system performance in a Southwest Asia (SWA) scenario. Some Aircraft characteristics were grouped into functional sets, while others were considered individually. After screening one characteristic, reliability, with a two-level factorial experiment, a Box-Behnken design was used to estimate second-order metamodels. A stepwise regression procedure indicated that, if attrition rates are ignored, airlift system performance is most impacted by the aircraft's size, survivability, cruise speed, and ability to operate on short fields. The SWA scenario used in this study covers a large …

Patient Scheduling And Aircraft Routing For Strategic Aeromedical Evacuation, Michael J. Loftus

Theses and Dissertations

The objective of this study is to develop an approach that would assign patients to aeromedical evacuation aircraft and route each aircraft to a single CONUS airport. The goal is to minimize total patient wait time. A heuristic algorithm is developed which exploits the structure of the problem. The first subproblem solved is the assignment of aircraft to airports. This subproblem is solved using integer programming and the results are input into the second subproblem. The second subproblem is the patient to aircraft assignment problem. This subproblem minimizes patient wait time and is solved using network flow programming. The two …

Estimating Test Range Capacity, Paul A. Mcdaniel

Theses and Dissertations

The main focus of this thesis effort was to develop a means to estimate the capacity of the test range complex at Eglin AFB, Florida. For the purposes of this study, test range capacity was defined as the maximum number of missions, of a given set, that could possibly be supported by range resources on any given day. In trying to determine this number, the complexities of the overall multi-resource constrained scheduling problem dictated a more practical approach be taken in modeling the allocation process of range resources to test missions. Therefore, a series of three single-resource, 0-1 integer programming …

The Battle Of Little Round Top: An Analysis Of Battle Alternatives Through Commercial Wargames, John J. Mcguiness

Theses and Dissertations

This thesis examines the problem of whether one can use commercial wargames as a tool for historical research. The research examines two wargames dealing with the battle of Little Round Top: Gettysburg: The Turning Point and Thunder at the Crossroads. This research emphasized the need to analyze the wargame's structure prior to playing the game. This will avoid a possible mistake of drawing a conclusion about a particular driver in the battle which may not be from the historical situation but rather an inevitable outcome produced by the model's basic assumptions. Additionally, quantitative measures of time lines, casualty rates, and …

A Fuzzy Logic Optimal Control Law Solution To The Cmmca Tracking Problem, Randy E. Nelson

Theses and Dissertations

The Air Force uses the C-18 Cruise Missile Mission Control Aircraft (CMMCA) to radar track cruise missiles (CM) during test flights. Because of the complexity of the CM flight profiles, maintaining radar coverage at all times is very difficult. This thesis attempted to apply optimal control theory to construct a simulation providing 100% radar coverage. The simulation was divided into ten second intervals, and fuzzy logic was used at the start of each interval to determine the set point, i.e., that point in space where the CMMCA should be in ten seconds. The set point calculation's fuzzy logic balanced CMMCA …

Models For The Optimization Of Air Refueling Missions, Clayton H. Pflieger

Theses and Dissertations

This research follows A. Yamani's work on the problem of minimizing total fuel costs for airlift missions that require in-flight refueling. Yamani's major assumptions were removed and the resulting enhanced formulation was applied the the original problem and the related problem of maximizing allowable cabin load. This optimization is accomplished selecting the rendezvous point and initial fuel for each aircraft. The formulation considers a C-141B airlifter refueled once by a KC-135E tanker. Flight is assumed to be at constant altitude and follow great-circle routes. The fuel costs of climb and cruise flight are modeled as functions of gross weight, while …

The Integration Of Tanker Aircraft Into Aslar, John S. Stieven

Theses and Dissertations

The purpose of this study was to analyze the proposed addition of heavy KC-135 tanker aircraft to the United States Air Force Aircraft Surge Launch and Recovery (ASLAR) instrument approach system. The Air Force Communications Command, which oversees ASLAR operations, will use these results to determine if KC-135 aircraft should be permitted to fly ASLAR approaches. A SIMSCRIPT II.5 animated simulation model was developed to simulate the Runway 26 approach at Seymour Johnson Air Force Base under a variety of wind conditions. This model was expanded to show the feasibility of KC-135s flying ASLAR approaches and to determine proper controller …

An Empirical Evaluation Of Five Circular Error Probable Estimation Techniques And A Method For Improving Them, William L. Tongue

Theses and Dissertations

This study compared five CEP estimation techniques under the assumption 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 sample size, bias, correlation, and ellipticity in terms of three measures of effectiveness: Mean relative error (RE), variance of RE, and mean squared error (MSE) of RE. In general, it was found that sample size was the most significant parameter in determining the best CEP method. Mean RE provided a 'strong' distinction between estimators, while variance and MSE provided 'weak' distinctions between estimators. …

Hoph Bifurcation In Viscous, Low Speed Flows About An Airfoil With Structural Coupling, Mark J. Lutton

Theses and Dissertations

The locations of Hopf bifurcation points associated with the viscous, incompressible flow about a NACA 0012 airfoil with structural coupling are computed for very low Reynolds numbers (<2000). A semi-implicit, first-order-accurate time integration algorithm is employed to solve the stream function-vorticity form of the Navier-Stokes equations. The formulation models the inclusion of simple structural elements affixed to the airfoil and captures the resulting airfoil motion. The equations describing the airfoil motion are integrated in time using a fourth-order Runge-Kutta algorithm. The dissertation is divided into two parts. In part one, numerical experiments are performed in the laminar regime to determine if the structural model of the airfoil has an effect upon the location of the Hopf bifurcation point when compared with the fixed airfoil. Results are reported for a variety of structural characteristics, including variations of torsional and linear spring constants, inertial properties, structural coupling, and structural damping. The structure of the solution space is explored by means of phase plots. In part two, the Baldwin-Lomax turbulence model is implemented to model turbulent flow. A numerical effort is made to predict the onset of unsteady flow.

Terrain Classification In Sar Images Using Principal Components Analysis And Neural Networks, Mahmood R. Azimi-Sadjadi, Saleem Ghaloum, R. Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

The development of a neural network-based classifier for classifying three distinct scenes (urban, park and water) from several polarized SAR images of San Francisco Bay area is discussed. The principal component (PC) scheme or Karhunen-Loeve (KL) transform is used to extract the salient features of the input data, and to reduce the dimensionality of the feature space prior to the application to the neural networks. Employing PC scheme along with polarized images used in this study, led to substantial improvements in the classification rates when compared with previous studies. When a combined polarization architecture is used the classification rate for …

Assessment Of 1991 Nehrp Provisions For Nonstructural Components And Recommended Revisions, Tsuteh Soong, Genda Chen, Z. Wu, R. H. Zhang, M. Grigoriu

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

As one part of the 1994 update effort of the 1991 NEHRP provisions, the seismic design force formulas for nonstructural components as they exist in the 1991 provisions are critically assessed and some of their shortcomings are identified. Various levels of improvements to these formulas are then presented which, on the one hand, preserve the equivalent lateral force format for design applicability and, on the other, correct some of the deficiencies on the basis of analyses, experimental results and observation data from past earthquakes.

Based on different interpretations of the component seismic coefficients as well as different degrees of simplicity …

Field Performance Evaluation Of Precast Concrete Box Culverts, Aluminum Culverts, And Galvanized Metal Arches And Pipe Arches, L. John Fleckenstein, David L. Allen, R. Clark Graves

Kentucky Transportation Center Research Report

Reported herein are the field performances of three different classes of culverts. The study included precast concrete boxes, precast arch culvert, aluminum boxes and pipe culverts, and several shapes of galvanized metal culverts. A total of 82 culverts were inspected throughout the state of Kentucky. Culverts were inspected in all 12 highway districts. A total of 15 precast concrete structures, 11 aluminum structures, and 56 galvanized metal structures were evaluated. This report discusses the distress observed in the three different classes of culverts and recommendations for future installations and possible maintenance schema for the existing culverts are included.

Evaluation Of Diamond Grade Reflective Sheeting, Kenneth R. Agent

Kentucky Transportation Center Research Report

The objective of this project was to monitor the performance of the diamond grade sheeting when used on both typical traffic signs and construction signs. The durability, appearance, and reflectivity of the signs were monitored. Diamond grade sheetings used on typical traffic signs were evaluated over a two-year period with construction signs evaluated over an 18-month period.

Diamond grade sheeting was found to provide increased reflectivity compared to high intensity sheeting with no problems noted related to durability or appearance. However, the cost of the diamond grade sheeting would limit its use to situations where brighter, wider-angle reflective sheeting is …

Design Of A Hardware Discrete Event Simulation Coprocessor, David W. Daniel

Theses and Dissertations

A hardware discrete event simulation (DES) coprocessor was designed to eliminate synchronization overhead as a possible bottleneck. The target architecture is an eight node Intel iPSC/2 Hypercube, but this design has application to future CPU designs that wish to incorporate on-chip architectural features to better support parallel processor synchronization. A structural description of a general-purpose DES hardware coprocessor is given with approximately 90 percent of the components written at the gate level. The remaining components use low-level behavioral descriptions. While the DES coprocessor microcode implements the Chandy-Misra protocol, general-purpose support for a wide-range of protocols was a primary hardware design …