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Articles 511 - 540 of 602
Full-Text Articles in Operational Research
Modified Anderson-Darling And Cramer-Von Mises Goodness-Of-Fit Tests For The Normal Distribution, David A. Gwinn Sr.
Modified Anderson-Darling And Cramer-Von Mises Goodness-Of-Fit Tests For The Normal Distribution, David A. Gwinn Sr.
Theses and Dissertations
New techniques for calculating goodness-of-fit statistics for normal distributions with parameters estimated from the sample are investigated. Samples are generated for a Normal(0,1) distribution. Critical values are calculated for five modifications to the Anderson-Darling statistic and five modifications to the Cramer-Von Mises statistic. An extensive power study is done to test the power of the new statistics versus the power of the unmodified statistics. Powers of six of the new statistics show minimal to no improvement, two of the new statistics show a marked decrease in power, and two of the new statistics show an overall increase in power over …
Spartan Ii: An Instructional High Resolution Land Combat Model, Edwin H. Harris Jr.
Spartan Ii: An Instructional High Resolution Land Combat Model, Edwin H. Harris Jr.
Theses and Dissertations
This project improved SPARTAN, a high resolution land combat model demonstrator. SPARTAN was originally developed as a hands-on trainer for land combat modeling students because there were no models specifically designed to teach the analysts how the models function. SPARTAN is built to demonstrate the techniques used in the current generation of US Army high resolution models. Like the original, the model is primarily a small scale attrition (both direct and indirect fire) model. The model represents 12 soldiers involved in the following processes: target search, target selection, direct fire engagement, indirect fire engagement, movement, reaction to fire, obstacle breaching, …
A Statistical Analysis Of Terrorism And Instability In Latin America, Juan A. Hurtado
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
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
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
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
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
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
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 …
Theater Airlifter Survivability On The Ground, Michael A. Silver
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
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 …
The Use Of Simulation To Evaluate Strategic Aeromedical Evacuation Policy And Planning, Charles W. Wolfe Jr.
The Use Of Simulation To Evaluate Strategic Aeromedical Evacuation Policy And Planning, Charles W. Wolfe Jr.
Theses and Dissertations
Strategic aeromedical evacuation (AE) of casualties from the theater of operations to the CONUS during wartime is a complex operation that involves the integration of medical personnel and policies with airlift concepts and capabilities. Military analysts within the Air Mobility Command Analysis Group (AMC/XPY) have traditionally used deterministic linear programming techniques to estimate the number of aircraft the United States Air Force (USAF) requires for given contingency scenarios. However, this group has yet to develop a stochastic approach to validate their resource recommendations, and more importantly, to study the interrelationships between key factors comprising strategic aeromedical evacuation. As the possibility …
A Comparison Of Variable Selection Criteria For Multiple Linear Regression: A Second Simulation Study, David P. Woollard
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
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
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
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 Tactical Airlifter Characteristics And Their Impact On Theater Airlift System Performance, John J. Koger
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
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 …
A Fuzzy Logic Optimal Control Law Solution To The Cmmca Tracking Problem, Randy E. Nelson
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 …
The Integration Of Tanker Aircraft Into Aslar, John S. Stieven
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
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. …
Enhancements To The Animated Tutor For Air Combat Simulation, David A. Legge
Enhancements To The Animated Tutor For Air Combat Simulation, David A. Legge
Theses and Dissertations
This study investigates the use of the Ada programming language in combat modeling. It takes an existing combat model, the Animated Tutor for Air Combat Simulation (ATACS), and re-writes it into Ada. The new model also includes enhancements to the original model. ATACS+, as it is now called, is used as a learning tool in combat modeling classes at the Air Force Institute of Technology. ATACS+ consists of a preprocessor and a model, complete with two and three-dimensional graphics and engagement status reports. Conclusion are made about Ada's suitability for combat modeling, some of the features of Ada which can …
A Modified Chi-Squared Goodness-Of-Fit Test For The Three-Parameter Gamma Distribution With Unknown Parameters, Thomas J. Sterle
A Modified Chi-Squared Goodness-Of-Fit Test For The Three-Parameter Gamma Distribution With Unknown Parameters, Thomas J. Sterle
Theses and Dissertations
A modified chi-squared goodness-of-fit test was created for the gamma distribution in the case where all three parameters must be estimated from the sample. Critical values are generated using a Monte Carlo simulation procedure with 5000 repetitions each. Random samples of 8 different sizes were drawn from gamma distributions with shape parameters 1, 1.5, 2., and 2.5. The shape, scale, and location parameters were then estimated from each sample, using an iterative technique combining the maximum likelihood and minimum distance methods, enabling, computation of the chi-squared statistics and critical values. The same process is used to generate random samples, parameter …
Identification Of The Initial Transient In Discrete-Event Simulation Output Using The Kalman Filter, Mark A. Gallagher
Identification Of The Initial Transient In Discrete-Event Simulation Output Using The Kalman Filter, Mark A. Gallagher
Theses and Dissertations
Data truncation is a commonly accepted method of dealing with initialization bias in discrete-event simulation. Algorithms for determining the appropriate initial-data truncation point for univariate and multivariate output are proposed. The techniques entail averaging across replications and estimating a steady-state output model in a state-space framework. Using the estimated model, Multiple Model Adaptive Estimation (MMAE), which uses Kalman filters with different parameter vectors, is applied. Based on the filters' residuals, the conditional probabilities of each filter's specific parameter vector being correct are determined. The MMAE parameter estimates are the probabilistic- weighted average of the filters' assumed parameter vectors. The estimated …
An Interactive Life Cycle Cost Forecasting Tool, Nicolas M. Habash
An Interactive Life Cycle Cost Forecasting Tool, Nicolas M. Habash
Theses and Dissertations
This thesis is about computing life cycle cost and culminates with a life cycle cost forecasting tool (software). The software is written in FORTRAN 77 and uses IMSL subroutine extensively for random number generation from various distributions. The algorithm can compute life cycle cost for the following types of cost elements: constant, stochastic, and cost estimating relationships (CERs). The use of a trapezoid approximation of payment allocation is allowed. Percent allocation of payments is also allowed and is recommended where the trapezoid fails to correctly represent the payment schedule. The CER algorithm handles cost data that was estimated in base …
An Analysis Of Usspacecom's Space Surveillance Network (Ssn) Sensor Tasking Methodology, Jeff M. Berger, Joseph B. Moles, David G. Wisley
An Analysis Of Usspacecom's Space Surveillance Network (Ssn) Sensor Tasking Methodology, Jeff M. Berger, Joseph B. Moles, David G. Wisley
Theses and Dissertations
This study provides the basis for the development of a cost/benefit assessment model to determine the effects of alterations to the Space Surveillance Network (SSN) on orbital element (OE) set accuracy. It provides a review of current methods used by NORAD and the SSN to gather and process observations, an alternative to the current Gabbard classification method, and the development of a model to determine the effects of observation rate and correction interval on OE set accuracy. The proposed classification scheme is based on satellite J2 perturbations. Specifically, classes were established based on mean motion, eccentricity, and inclination Since J2 …
Analysis Of Whole-Sky Imager Data To Determine The Validity Of Pcflos Models, Richard W. Boltz, George R. Kather
Analysis Of Whole-Sky Imager Data To Determine The Validity Of Pcflos Models, Richard W. Boltz, George R. Kather
Theses and Dissertations
Models used to predict the probability of a cloud-free line-of-sight (PCFLOS) from the ground to space have existed since the 1960s. Unfortunately, an adequate data set has not been available to check the validity of these models until the deployment of the Whole-Sky Imager (WSI) system in 1989. Now that a three-year database has been collected from the WSI system, it is possible to validate, or refute, the existing models. This study investigates the most generally accepted models. Specifically, we investigate three questions: (1) Is the Lund and Shank-lin PCFLOS model assumption of azimuthal independence valid; (2) Does the Lund …
Analysis Of Titan Iv Launch Responsiveness, Michael T. Dunn
Analysis Of Titan Iv Launch Responsiveness, Michael T. Dunn
Theses and Dissertations
This research investigates the feasibility of developing responsive space systems through responsive launch operations with the Titan IV, the only expendable heavy-lift launch vehicle in the United States inventory. A definition for responsive launch has not been firmly established by Air Force Space Command for this launch vehicle. For benchmark purposes, this study uses the responsive launch definition contained in the proposal request for the Medium Launch Vehicle Ill: launch vehicle ignition within 60 days of mission need notification. Titan IV launch processing at Cape Canaveral Air Force Station (CCAFS), Florida currently requires in excess of six months, rendering Titan …
A Model Of Global Positioning System (Gps) Master Control Station (Mcs) Operations, David N. Koster
A Model Of Global Positioning System (Gps) Master Control Station (Mcs) Operations, David N. Koster
Theses and Dissertations
The United States Air Force's Navstar Global Positioning System (GPS) provides high-accuracy space-based navigation and time distribution to suitably- equipped military and civilian users. The system consists of earth-orbiting satellites and a world-wide network of ground stations. A single operational control center, the GPS Master Control Station (MCS) monitors, maintains, and commands the GPS satellite constellation. The on-going deployment of the complete satellite constellation and recent changes in the operational crew structure may invalidate previously used planning and management paradigms. There is currently no analytical method for predicting the impact of these and other environmental changes on system parameters and …