Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 97861 - 97890 of 198044

Full-Text Articles in Engineering

Visual-Ins Using A Human Operator And Converted Measurements, Turner J. Montgomery Mar 2016

Visual-Ins Using A Human Operator And Converted Measurements, Turner J. Montgomery

Theses and Dissertations

A method human operated INS aiding is explored in which the pilot identifies and tracks a ground feature of unknown position over a short measurement epoch using an E/O sensor. One then refers to Visual-INS. In contrast to current research trends, a human operator is entrusted with visually tracking the ground feature. In addition, a less conventional measurement linearization technique is applied to generate “converted” measurements. A linear regression algorithm is then applied to the converted measurements providing an estimate of the INS horizontal velocity error and accelerometer biases. At the completion of the measurement epoch, the INS is corrected …

Go to article

A Comparative Analysis Of Ieee 802.15.4 Adapters For Wireless Range Finding, Andrew P. Seitz Mar 2016

A Comparative Analysis Of Ieee 802.15.4 Adapters For Wireless Range Finding, Andrew P. Seitz

Theses and Dissertations

ZigBee wireless networks have become increasingly prevalent over the past decade. Based on the IEEE 802.15.4 low data rate wireless standard, ZigBee offers low-cost mesh connectivity in hospitals, refineries, building automation, and critical infrastructure. This thesis explores two ZigBee Received Signal Strength Indicator (RSSI)-based rangefinding tool sets used for assessing wireless network security: Z-Ranger and Zbfind. Z-Ranger is a new tool set developed herein for the Microchip Zena Wireless Adapter that offers configurable distance estimating parameters and a RSSI resolution of 256 values. Zbfind is an application developed for the Atmel RZUSBstick with no configurable distance estimating parameters and a …

Go to article

Dynamic Network Security Control Using Software Defined Networking, Michael C. Todd Mar 2016

Dynamic Network Security Control Using Software Defined Networking, Michael C. Todd

Theses and Dissertations

This thesis develops and implements a process to rapidly respond to host level security events using a host agent, Software Defined Networking and OpenFlow updates, role based flow classes, and Advanced Messaging Queuing Protocol to automatically update configuration of switching devices and block malicious traffic. Results show flow table updates are made for all tested levels in less than 5.27 milliseconds and event completion time increased with treatment level as expected. As the number of events increases from 1,000 to 50,000, the design scales logarithmically caused mainly by message delivery time. Event processing throughput is limited primarily by the message …

Go to article

Multihop Rendezvous Algorithm For Frequency Hopping Cognitive Radio Networks, John A. Pavlik Mar 2016

Multihop Rendezvous Algorithm For Frequency Hopping Cognitive Radio Networks, John A. Pavlik

Theses and Dissertations

Cognitive radios allow the possibility of increasing utilization of the wireless spectrum, but because of their dynamic access nature require new techniques for establishing and joining networks, these are known as rendezvous. Existing rendezvous algorithms assume that rendezvous can be completed in a single round or hop of time. However, cognitive radio networks utilizing frequency hopping that is too fast for synchronization packets to be exchanged in a single hop require a rendezvous algorithm that supports multiple hop rendezvous. We propose the Multiple Hop (MH) rendezvous algorithm based on a pre-shared sequence of random numbers, bounded timing differences, and similar …

Go to article

Comparison Of Radio Frequency Distinct Native Attribute And Matched Filtering Techniques For Device Discrimination And Operation Identification, Barron D. Stone Mar 2016

Comparison Of Radio Frequency Distinct Native Attribute And Matched Filtering Techniques For Device Discrimination And Operation Identification, Barron D. Stone

Theses and Dissertations

The research presented here provides a comparison of classification, verification, and computational time for three techniques used to analyze Unintentional Radio- Frequency (RF) Emissions (URE) from semiconductor devices for the purposes of device discrimination and operation identification. URE from ten MSP430F5529 16-bit microcontrollers were analyzed using: 1) RF Distinct Native Attribute (RFDNA) fingerprints paired with Multiple Discriminant Analysis/Maximum Likelihood (MDA/ML) classification, 2) RF-DNA fingerprints paired with Generalized Relevance Learning Vector Quantized-Improved (GRLVQI) classification, and 3) Time Domain (TD) signals paired with matched filtering. These techniques were considered for potential applications to detect counterfeit/Trojan hardware infiltrating supply chains and to defend …

Go to article

Civil Engineer Company Grade Officer Training Needs Analysis For Contingency Operations, Brian S. Greszler Mar 2016

Civil Engineer Company Grade Officer Training Needs Analysis For Contingency Operations, Brian S. Greszler

Theses and Dissertations

In terms of active duty personnel, the USAF is the smallest it has ever been since its creation in 1947. With fewer personnel to accomplish essential tasks, the training of Airmen is more important than ever. Outdated and irrelevant training can lead to gaps in the knowledge of trainees. The purpose of this research was to analyze the training needs of Civil Engineer (CE) Company Grade Officers (CGOs) in the contingency environment. This was done by first conducting a Job Analysis (JA). The JA resulted in a list of 36 critical tasks and 58 important Knowledge, Skills, and Abilities (KSAs). …

Go to article

Radiation Effects In Thin Film Hexagonal Boron Nitride, Nathaniel M. Kaminski Mar 2016

Radiation Effects In Thin Film Hexagonal Boron Nitride, Nathaniel M. Kaminski

Theses and Dissertations

The radiation response of 2 nm and 12 nm hexagonal boron nitride (hBN) thin film insulators was studied using metal insulator semiconductor (MIS) devices. Current-voltage, capacitance-voltage, and impedance spectroscopy measurements were compared to quantify changes in hBN resistance due to radiation damage. MIS devices exposed to a gamma total dose deposition of 3.1 Mrad(Si) from a Co- 60 source exhibited a small increase in hBN resistance and no observable C-V shift associated with charge trapping. MIS devices irradiated with 4.5 MeV silicon ions showed no significant resistivity decrease to a threshold fluence of 1 ×1012 for the 2 nm …

Go to article

Logistics Simulation For Long Duration Logistics Wargames, Kevin R. Cardenas Mar 2016

Logistics Simulation For Long Duration Logistics Wargames, Kevin R. Cardenas

Theses and Dissertations

Wargames were originally created to test wartime strategies against opposing forces within a short time frame. Due to the short duration design of these wargames, logistics were deemed irrelevant and it was incorrectly assumed that the warfighter would be logistically supported for the entire duration of the wargame. The purpose of this thesis is to provide insight to the value of capturing logistics within a wargame and to better model the increased requirement for Agile Combat Support. This research utilizes a logistics simulation tool and its outputs to conduct statistical analyses comparing a baseline scenario created to mirror the Joint …

Go to article

Characterization Of 2d Jammed Granular Memristive Copper Arrays, Len L. Kedrow Mar 2016

Characterization Of 2d Jammed Granular Memristive Copper Arrays, Len L. Kedrow

Theses and Dissertations

A novel sensor made of jammed granular memristive copper spheres was explored in an effort to develop a protection technology that could be used in non-proliferation treaty monitoring. The micro-copper spheres were annealed for various times at a constant temperature. SEM, EDS, and XPS were used to characterize the growth of the oxide coating. Electrical characterization of the device was done by confining the granular copper spheres to a two-dimensional plane using a unique test fixture capable of measuring I-V curves at the boundary of the circuit board using tungsten pillar electrodes. Electroforming of the copper spheres produced soft dielectric …

Go to article

Automated Sunspot Classification And Tracking Using Sdo/Hmi Imagery, Maclane A. Townsend Mar 2016

Automated Sunspot Classification And Tracking Using Sdo/Hmi Imagery, Maclane A. Townsend

Theses and Dissertations

Verification of an automated sunspot detection and classification algorithm is conducted utilizing two years of solar imagery from NASA's Solar Dynamics Observatory (SDO) satellite. Automated McIntosh classifications are compared against sunspot reports from the National Oceanic and Atmospheric Administration’s (NOAA) Space Weather Prediction Center (SWPC) using a three-tiered comparison metric. Statistical confidence is demonstrated for algorithm performance and consistency when compared against the SWPC data set, suggesting future applications of the algorithm will perform similarly. A sunspot tracking algorithm is added to the existing code and demonstrates reliable feature tracking for time periods out to four days between consecutive images. …

Go to article

Contingency Workload Demand Forecast Techniques For Cargo And Flying Hours, Calvin J. Bradshaw Iii Mar 2016

Contingency Workload Demand Forecast Techniques For Cargo And Flying Hours, Calvin J. Bradshaw Iii

Theses and Dissertations

Accurate forecasting of contingency workload demand for USTRANSCOM (USTC) is a herculean effort. Transportation Working Capital Fund (TWCF) managers rely on various subject matters outside and within the combatant command to estimate future workload. Since rates are set annually, when TWCF activities use incorrect or incomplete projections of workload, this leads to erroneous price structures and misaligned customer billing rates. The USTC leadership lacks the ability to accurately forecast workload demand, which is a key driver for service provider rate-setting. As a result, some customers perceive spiked rates and seek service from other competitors, which generates lost revenue, customer dissatisfaction …

Go to article

United States Air Force Officer Manpower Planning Problem Via Approximate Dynamic Programming, Amelia E. Bradshaw Mar 2016

United States Air Force Officer Manpower Planning Problem Via Approximate Dynamic Programming, Amelia E. Bradshaw

Theses and Dissertations

The United States Air Force (USAF) is concerned with managing its officer corps to ensure sufficient personnel for mission readiness. Manpower planning for the USAF is a complex process which requires making decisions about accessions. Uncertainty about officer retention complicates such decisions. We formulate a Markov decision process model of the Air Force officer manpower planning problem (AFO-MPP) and utilize a least squares approximate policy iteration algorithm as an approximate dynamic programming (ADP) technique to attain solutions. Computational experiments are conducted on two AFO-MPP instances to compare the performance of the policy determined with the ADP algorithm to a benchmark …

Go to article

Analysis Of Military Entry Control Point Queueing, Justin J. Dwyer Mar 2016

Analysis Of Military Entry Control Point Queueing, Justin J. Dwyer

Theses and Dissertations

Military Entry Control Facilities (ECFs) are unique service queues that are constrained by space, receive high peak traffic flow, and have a customer base that must receive service. Due to complexity of the interactions within the system, simulations provide input that would be impractical for quantitative experimentation. Our research examines relationships within the ECF in order to develop insights that could lead to more efficient daily operations. We focus the research on interactions that generate a queue length that would interfere with traffic flow surrounding the base. Examining the interactions between multiple arrival rates and service times as well as …

Go to article

A Response Surface Validation Of A Quantum Key Distribution Model, Jacob M. Ehrlich Mar 2016

A Response Surface Validation Of A Quantum Key Distribution Model, Jacob M. Ehrlich

Theses and Dissertations

The need for secure communication in the presence of an adversary introduced the field of cryptology -- the practice and study of techniques for secure communication. A common method to secure communication is to distribute a secret key among authorized parties so they can encrypt and decrypt messages between each other. By doing so, ideally, any messages intercepted by a third party are meaningless. An innovative technique to distribute a shared key is Quantum Key Distribution (QKD). QKD uses laws of quantum mechanics to generate and distribute such keys. The purpose of this thesis is to validate an existing mathematical …

Go to article

Heterogeneous Air Defense Battery Location: A Game Theoretic Approach, Nicholas T. Boardman Mar 2016

Heterogeneous Air Defense Battery Location: A Game Theoretic Approach, Nicholas T. Boardman

Theses and Dissertations

The Unites States and its allies confront a persistent and evolving threat from missile attacks as nations around the world continue to invest and advance their current capabilities. Within the air defense context of a missile-and-interceptor engagement, a challenge for the defender is that surface to air interceptor missile batteries often must be located to protect high-value targets dispersed over a vast area, subject to an attacker observing the disposition of batteries prior to developing and implementing an attack plan. To model this scenario, we formulate a two-player, three-stage, perfect information, sequential move, zero-sum game that accounts for, respectively, a …

Go to article

Simulation Of Modeling Sortie Generation Process In Turaf, Bahadir Aykiri Mar 2016

Simulation Of Modeling Sortie Generation Process In Turaf, Bahadir Aykiri

Theses and Dissertations

Simulation is a useful technique for engineers and operations researchers. One of the primary advantages of simulation models is that they are able to provide users with practical feedback when analyzing real-world systems. This thesis builds a discrete event simulation of the sortıe generatıon process, to help decision makers in performing analyses regarding quantity of manpower, bottlenecks in supply and maintenance activities; as well as utilization of maintenance manpower, cost and number of sorties produced in a specific time. We only model one aircraft system with four Line Replacement Units (LRU), but any system and its LRUs can be included …

Go to article

The Impact Of Reducing Full Time Support Positions In The U.S. Army National Guard And Reserves, Lucas J. Lease Mar 2016

The Impact Of Reducing Full Time Support Positions In The U.S. Army National Guard And Reserves, Lucas J. Lease

Theses and Dissertations

The United States Army is at a point in its history in which it, along with the other branches of the military, are experiencing cuts, constraints and a tightening of resources. The days of seemingly large budgets, abundant financial resources and high amounts of manpower are becoming a thing of the past. As the government reduces the allocations to the military, it is examining ways to reduce costs and improve its financial prospects. One of the positions examined for reduction or outright elimination is the full time support position in the U.S. Army National Guard (ARNG) and Reserves (USAR). The …

Go to article

Long-Term Impacts Of Military Drawdown On The Industrial Base, Anton H. Martyn Mar 2016

Long-Term Impacts Of Military Drawdown On The Industrial Base, Anton H. Martyn

Theses and Dissertations

Since World War II, competition in the defense industry has fallen by over 90 percent. Over half of contracts currently executed by the United States Navy and Air Force are awarded without any competition. With the recent defense budget cuts, and an extended period of reduced defense spending ahead, more of which is going to sustainment and overhead than ever before, each year prime contractors are fighting over an even smaller piece of the procurement pie, which could have a deleterious effect on national security if these contractors go out of business or further consolidate through mergers. This study used …

Go to article

Epidemiology, Cost, And Aircraft Choice For Aeromedical Evacuation In Africom, Daniel A. Griffith Mar 2016

Epidemiology, Cost, And Aircraft Choice For Aeromedical Evacuation In Africom, Daniel A. Griffith

Theses and Dissertations

A significant shortfall exists in the medical capability provided to US Service members deployed to the African Area of Responsibility because of unknown epidemiology, large distances, limited resources, and high patient movement cost. The first step in closing this gap is to understand the types, demographics, diagnoses, and distribution of the patients requiring aeromedical evacuation. This research examined the DoD’s aeromedical evacuation missions from Africa between 2010 and 2014. Of the 274 patients and 170 missions identified from available data, a gap is evident in aeromedical evacuation capability with over 23% of Priority patients and almost 10% of Urgent patients …

Go to article

Overhaul Facility Planning And Control Tool Selection And Implementation Analysis, Santiago L. Martin Mar 2016

Overhaul Facility Planning And Control Tool Selection And Implementation Analysis, Santiago L. Martin

Theses and Dissertations

The Argentine Air Force Materiel General Directorate (AAFMGD) has initiated an effort to assure logistical support and to gradually increase the productivity and efficiency of related processes. Within the efforts of increased productivity and efficiency over the AAF Overhauling Facilities, the Planning and Control Departments (PCD) became targets for improvements. These departments are tasked with providing the best certainty and visibility of all assets within their facilities to feed the logistics pipeline, and better support air operations. This thesis, sponsored by the MGD, is focused on achieving improvements in the PCD processes, through an academically rigorous evaluation of confounding factors …

Go to article

A "Big Bang" Versus A "Small Bang" Approach: A Case Study Of The Expeditionary Combat Support System (Ecss) And The Maintenance, Repair, And Overhaul Initiative (Mroi), George B. Lafiguera Mar 2016

A "Big Bang" Versus A "Small Bang" Approach: A Case Study Of The Expeditionary Combat Support System (Ecss) And The Maintenance, Repair, And Overhaul Initiative (Mroi), George B. Lafiguera

Theses and Dissertations

In 2003, the United States Air Force embarked on one of the largest and most comprehensive logistical transformation to delineate the logistics community’s strategy for supporting the warfighter. A key aspect of this campaign plan was to leverage information technology through an enterprise resource planning (ERP) solution called the Expeditionary Combat Support System (ECSS), a “big-bang” approach. In early 2012, the ECSS program was cancelled mainly due to uncontrollable increases in costs and schedule overruns. In late 2012, the Air Force Sustainment Center (AFSC) launched the Maintenance, Repair, and Overhaul initiative (MROi), a “small-bang” approach, to increase enterprise visibility and …

Go to article

Using Multiple Objective Decision Analysis To Position Federal Product And Service Codes Within The Kraljic Portfolio Matrix, Robert T. Montgomery Mar 2016

Using Multiple Objective Decision Analysis To Position Federal Product And Service Codes Within The Kraljic Portfolio Matrix, Robert T. Montgomery

Theses and Dissertations

Despite the best efforts of the Federal Government to implement strategic sourcing, recent Government Accountability Office (GAO) reports highlight major procurement deficiencies and encourage the use of commercial best practices to identify and reap substantial savings. The Kraljic Portfolio Matrix (KPM) is considered the premier tool for purchasing organizations to determine which commercial best practices to utilize for different categories of spend. However, critics of the KPM point to its lack of analytical rigor and the absence of a simplistic quantitative methodology for implementation. The Air Force Installation Contracting Agency (AFICA), the centralized procurement arm for 79 USAF installations worldwide, …

Go to article

Modeling And Economy’S Dynamics And External Influences Through A System Of Differential Equations, Thomas M. Dickey Mar 2016

Modeling And Economy’S Dynamics And External Influences Through A System Of Differential Equations, Thomas M. Dickey

Theses and Dissertations

This research proposes a methodology to develop models for the greater understanding of the application of the economic instrument of national power through a selection of factors that define the economic condition of a country. The major components of an economy are identified as GDP per capita, a treasury bond yield, and a major stock market index. The components have interconnected dynamics along with external influences from the United Stated Federal Funds Rate and foreign direct investment. These connections are considered through a metamodel in the form of a system of differential equations which is solved as an inverse problem. …

Go to article

Sortie Generation Simulation Of A Fighter Squadron, Abdurrahman Sevimli Mar 2016

Sortie Generation Simulation Of A Fighter Squadron, Abdurrahman Sevimli

Theses and Dissertations

The Turkish Air Force utilizes several fighter squadrons to enhance its military capabilities. One of the most critical challenges for these squadrons is generating sorties to meet the currency and demand during both peacetime and wartime. This sortie generation process directly affects the success of both training and operations. In this study, this process is assessed using a discrete event simulation. Air Force decision makers require a simulation tool to conduct “what-if” analysis on how potential changes in the environment affect an F-16 fighter squadron’s sortie generation process. Creating a usable simulation provides decision makers with a flexible tool to …

Go to article

Methods To Address Extreme Class Imbalance In Machine Learning Based Network Intrusion Detection Systems, Russell W. Walter Mar 2016

Methods To Address Extreme Class Imbalance In Machine Learning Based Network Intrusion Detection Systems, Russell W. Walter

Theses and Dissertations

Despite the considerable academic interest in using machine learning methods to detect cyber attacks and malicious network traffic, there is little evidence that modern organizations employ such systems. Due to the targeted nature of attacks and cybercriminals’ constantly changing behavior, valid observations of attack traffic suitable for training a classifier are extremely rare. Rare positive cases combined with the fact that the overwhelming majority of network traffic is benign create an extreme class imbalance problem. Using publically available datasets, this research examines the class imbalance problem by using small samples of the attack observations to create multiple training sets that …

Go to article

An Examination Of Economic Metrics As Indicators Of Air Force Retention, Helen L. Jantscher Mar 2016

An Examination Of Economic Metrics As Indicators Of Air Force Retention, Helen L. Jantscher

Theses and Dissertations

Fluctuations in the economy can cause military recruitment and retention plans to go awry. By focusing on various economic metrics, it is possible to anticipate changes in retention rates for specific Air Force Specialty Codes (AFSCs). To address the challenge of maintaining a robust and mission capable Air Force, a correlation analysis is employed to determine the relationship between certain economic indicators and AFSC retention rates. As one might suspect, retention rates follow the trend of decreasing when the economy is strong. Of interest, we found two AFSCs which go against this trend. Namely, the retention rates for officers in …

Go to article

Rate Setting Analysis: A Statistical Approach To Outlier Analysis In The Rate Setting Process Within The United States Transportation Command, Warren B. Mcgriff Mar 2016

Rate Setting Analysis: A Statistical Approach To Outlier Analysis In The Rate Setting Process Within The United States Transportation Command, Warren B. Mcgriff

Theses and Dissertations

The rate setting process implemented by the USTRANSCOM J8 Program Analysis & Financial Management Directorate (USTC J8 or TCJ8) is of importance, as accurate rates yield proper and equitable recoupment of costs from customers and ensure USTC can achieve an accurate Net Operating Result (NOR) in each given year. This research sought to identify areas in which the current rate setting methodology can be improved. We initially examined the use of six months of historical cost data versus a full year of data to set rates, concluding that there is not a statistically significant difference with respect to their relative …

Go to article

Increased Capacity Utilizing Aggregation And Consolidation Of Contingency Cargo, Cassidy L. Wilson Mar 2016

Increased Capacity Utilizing Aggregation And Consolidation Of Contingency Cargo, Cassidy L. Wilson

Theses and Dissertations

Maximizing use of limited airlift assets is a common problem during large contingency operations. Requirements often exceed airlift capacity and fiscal constraints driving the need to aggregate conveyance loads both within and across business lines (Unit Line Number (ULN), Special Assignment Airlift Mission (SAAM), and sustainment). Current methods of consolidation are completed by planners at the 618th Air Operations Center. This process is completed by piecing email correspondence and making individual localized decisions which are not always consistent with big picture efficiency. United States Transportation Command requested a study to create standard business rules or a methodology that can benefit …

Go to article

A Logistic Regression And Markov Chain Model For The Prediction Of Nation-State Violent Conflicts And Transitions, Nicholas Shallcross Mar 2016

A Logistic Regression And Markov Chain Model For The Prediction Of Nation-State Violent Conflicts And Transitions, Nicholas Shallcross

Theses and Dissertations

Using open source data, this research formulates and constructs a suite of statistical models that predict future transitions into and out of violent conflict and forecasts the regional and global incidences of violent conflict over a ten-year time horizon. A total of thirty predictor variables are tested and evaluated for inclusion in twelve conditional logistic regression models, which calculate the probability that a nation will transition from its current conflict state, either In Conflict or Not in Conflict, to a new state in the following year. These probabilities are then used to construct a series of nation-specific Markov chain models …

Go to article

Determining The Degree Of The Routinization Of Additive Manufacturing In The Air Logistics Complexes, Candis A. Woods Mar 2016

Determining The Degree Of The Routinization Of Additive Manufacturing In The Air Logistics Complexes, Candis A. Woods

Theses and Dissertations

Fiscal constraints have affected the USAF’s spending and sustainment of weapons systems that are being utilized beyond their programmed life cycle; therefore, it is imperative that processes be given the critical eye for improvement, innovative approaches, and/or best practice implementation. The AFSC, part of the AFMC, has embarked on a groundbreaking effort to transform operations and leverage industry best practices, while maintaining focus on warfighter support to create “The AFSC Way.” The AFSC Way is based on a shared leadership model that emphasizes speed, safety, and quality, which gives way to innovative ideas and new technologies in order to achieve …

Go to article

First Prev Next Last