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Theses and Dissertations

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A Network Flow And Goal Programming Approach To Modeling The Impact Of Pre-Accession Training To The Trained Personnel Requirements Process, William J. Beveridge Mar 1991

A Network Flow And Goal Programming Approach To Modeling The Impact Of Pre-Accession Training To The Trained Personnel Requirements Process, William J. Beveridge

Theses and Dissertations

HQ ATC was tasked to analyze the impact of pre-accession training to the Trained Personnel Required (TPR) and training production process. Pre- accession training is a policy of providing contracted initial skills training to enlistees prior to entering basic military training. The purpose of this study was to develop a method to model the impact of pre-accession training. A network modeling and goal programming approach was used. Comparisons between the current training policy and a pre-accession training policy were made. Sensitivity was conducted on the impact of a balk rate on the new policy. The balk rate is the percent …

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Thermo-Mechanical Fatigue Of A Fiber Reinforced Titanium Aluminide Composite, Mark A. Bates Mar 1991

Thermo-Mechanical Fatigue Of A Fiber Reinforced Titanium Aluminide Composite, Mark A. Bates

Theses and Dissertations

The thermo-mechanical fatigue behavior of a specific unidirectional fiber reinforced titanium aluminide composite was investigated. Three test specimens were subjected to in-phase thermo-mechanical cycling and four to out- of-phase thermo-mechanical cycling. The applied maximum mechanical stresses ranged from 500-800 MPa. The stress ratio of 0.1 was used for all tests. The temperature range was from 150-650 C and the resulting fatigue lives were in the 58-1487 cycles range. The out-of-phase test specimens failed sooner compared to their respective in-phase counterparts. In order to find out why, the test results were analyzed using a simple micromechanics analysis and compared. The fracture …

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A Prolog-Based System For Hardware Verification, Kevin L. Sparks Mar 1991

A Prolog-Based System For Hardware Verification, Kevin L. Sparks

Theses and Dissertations

With the expanding number of components provided on a single digital chip, verification of digital designs is becoming a major problem. The more circuits one places on a single chip, the greater the number of input/output combinations which need to be checked. A paper by Barrow in 1984 discusses a Prolog-based hierarchical formal verification system which he calls VERIFY. Barrow provided a lot of information on what VERIFY can and cannot do, and on projected enhancements. He does not, however, mention how VERIFY actually performs the task of formal verification. This thesis will provide a description of one possible implementation …

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A Solution Methodology For The Variable-Level Scheduling Problem, Dennis R. Benson Mar 1991

A Solution Methodology For The Variable-Level Scheduling Problem, Dennis R. Benson

Theses and Dissertations

This study looked at a specific scheduling problem for a Department of Defense agency. A heuristic algorithms was developed to solve a general variable-level scheduling problem and was applied to this specific problem. This heuristic used linear programming and integer programming to find the minimum number of weekly billable hours for five alternative schedules. The best alternative schedule was further developed into a spreadsheet designed, squad level, master schedule. The result of this study was a proposed schedule that would save the United States government 8.2% of their security costs for this one part of the governmental agency. These savings …

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Calculated Point Defect Properties Of The Intermetallic Compounds Nickel Titanium (Niti) And Iron Titanium (Feti), Russell T. Lutton Mar 1991

Calculated Point Defect Properties Of The Intermetallic Compounds Nickel Titanium (Niti) And Iron Titanium (Feti), Russell T. Lutton

Theses and Dissertations

Atomistic simulation with a modified version of the DYNAMO code was used to calculate the point defect properties of the intermetallic compounds nickel titanium and iron titanium. The calculated energies are believed to be experimentally accurate to within ± 0.1 eV. Vacant Ni or Fe lattice sites were preferred and had energies of 6.356 eV for NiTi and 5.899 eV for FeTi. Removing a Ti atom resulted in a neighboring antisite defect caused by migration of a Ni or Fe atom into the vacant Ti site. These configurations had energies of 7.024 eV for NiTi and 6.336 eV for FeTi. …

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Effects Of Colocation And Non-Colocation Of Sensors And Actuators On Flexible Structures, W. C. Lee Mar 1991

Effects Of Colocation And Non-Colocation Of Sensors And Actuators On Flexible Structures, W. C. Lee

Theses and Dissertations

This thesis compares the performance and robustness of colocated and non-colocated sensor/actuator pairs. Linear quadratic Gaussian and loop transfer recovery (LOG/LTR) procedures are used to design optimum controllers for three example problems. The first example is a single motion degree-of-freedom system having motion only about one axis. This type of system does not have any right half plane zeros for the non-colocated case; however, the thesis shows it behaves as a non minimum phase system. The second example is a Bernoulli-Euler beam which does not have RHP zeros. An optimum LOG/LTR controller can not improve the robustness of non minimum …

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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 Mar 1991

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 …

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Transfer Of 4gl Application From Ingres To Oracle, Adnan Altunisik Mar 1991

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 …

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The Boundary Element Method Applied To The Two Dimensional Stefan Moving Boundary Problem, Donald C. Vosika Mar 1991

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.

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A Common Interface Real-Time Multiprocessor Operating System For Embedded Systems, Michael S. Rottman Mar 1991

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 …

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An Automated Red Player For The Theater Warfare Exercise, Karl W. Kabanek Mar 1991

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 …

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Optimal Iterative Task Scheduling For Parallel Simulations, Joann M. Sartor Mar 1991

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. …

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A Computer Simulation Of Braitenberg Vehicles, Eric B. Werkowitz Mar 1991

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, …

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A Fully Coupled, Automated Formation Control System For Dissimilar Aircraft In Maneuvering Formation Flight, Paul R. Rohs Mar 1991

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 …

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A Navigation Reference System (Nrs) Using Global Positioning System (Gps) Aiding, Richard D. Stacey Mar 1991

A Navigation Reference System (Nrs) Using Global Positioning System (Gps) Aiding, Richard D. Stacey

Theses and Dissertations

To quantify the performance abilities of existing or proposed navigation systems, the U.S. Air Force has for the last several years compared the performance of the system under test to the performance of a baseline navigation system known as the Completely Integrated Reference Instrumentation System (CIRIS). CIRIS obtains a highly accurate navigation solution by combining the output from three major subsystems: inertial navigation system (INS) information, barometric altitude information, and range and range-rate data from ground transponders which have been precisely surveyed. Although the navigation solution produced by CIRIS is highly accurate, it will soon be inadequate as the standard …

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Investigation Of A Zero-One Integer Programming Approach To Automating The Scheduling Process At The Usaf Test Pilot School, Lisa M. Hassel Mar 1991

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 …

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Saber: A Theater Level Wargame, William F. Mann Iii Mar 1991

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 …

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The Modeling Of Employment Decisions For Peacetime Contingency Operations, Michael C. Wilmer Mar 1991

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 …

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The Utility Of Elliptical And Circular Confidence Regions For Hfdf Receivers, Paul T. Nemec Mar 1991

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 …

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The Development Of An Officer Training School Board Score Prediction Method Using A Multi-Board Approach, Sandra C. Niemi Mar 1991

The Development Of An Officer Training School Board Score Prediction Method Using A Multi-Board Approach, Sandra C. Niemi

Theses and Dissertations

One phase in the Officer Training School (OTS) selection process is meeting a selection board. Recruiting Services (HQ ATC/RS) currently uses a regression model (based on data from one board) to evenly distribute 'quality' among the different panels in the selection boards. HQ ATC/RS wanted a method of predicting board scores based on data from multiple boards. This study used the results from eighteen boards and 9215 applicants to develop and validate a multi-board regression model for each of five application categories. Comparisons between the two models showed mixed results. In two categories, non- rated operations and technical, the single-board …

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Analysis Of The Effects Of The Commander's Battle Positioning On Unit Combat Performance, Thomas I. Pratt Mar 1991

Analysis Of The Effects Of The Commander's Battle Positioning On Unit Combat Performance, Thomas I. Pratt

Theses and Dissertations

The purpose of this study was to determine the effect of the Commander's battle positioning on unit combat performance. Research was focused on analyzing the location of the Battalion/Task Force Commander during daytime deliberate attacks conducted at the U.S. Army's National Training Center, Fort Irwin, CA. Forty battles, from January 1986 to September 1989, provided the basis for this study. Information that described the Commander's location, a general description of the battle, and unit measures of effectiveness, was collected for each battle and put in a format that allowed for ease of analysis. This study database was explored using numerous …

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Enhancements To Pcrsm, Laurie M. Rouillard Mar 1991

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).

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Locating Direction Finders In A Generalized Search And Rescue Network, Jean M. Steppe Mar 1991

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 …

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An Interactive Life Cycle Cost Forecasting Tool, John A. Gibson Iv Mar 1991

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 …

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A Study Of Variables To Help Predict Navigator Training Success And Classification, Gary A. Hagler Mar 1991

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 …

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Development Of An Angular Distribution Function For The Study Of Atomic Lattice Structures Used In Atomistic Simulation, David Wesley Mar 1991

Development Of An Angular Distribution Function For The Study Of Atomic Lattice Structures Used In Atomistic Simulation, David Wesley

Theses and Dissertations

An angular distribution function (ADF) was developed as a tool to be used in atom simulation. The ADF lets us easily distinguish between different lattice structures for systems of atoms by looking at the distribution of bond angles. The ADF is also a useful tool for determining the amount of order in a system. First, model structures of simple cubic, FCC, BCC, and diamond were developed. Then, the ADF was used on these model structures so that a set of model graphs of the ADF could be used to compare to real systems. Finally, simulated systems of Ferric Titanate, Nickel …

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Hardware Upgrade Of A Segmented Drum Assay System, Claude A. Irvine Mar 1991

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 …

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A Study Of The Liquid-Solid Interface During Rapid Resolidification Of Cooper-Titanium Using Molecular Dynamics, Craig L. Loisel Mar 1991

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/ …

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High Altitude Neutral Particle Transport Using The Monte Carlo Simulation Code Mcnp With Variable Density Atmosphere, David L. Monti Mar 1991

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 …

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New Modified Anderson-Darling And Cramer-Von Mises Goodness-Of-Fit Tests For A Normal Distribution With Specified Parameters, Goksel Kahya Mar 1991

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% …

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